Publications by authors named "Yuan-Tsong Chen"

147 Publications

Association of an IGHV3-66 gene variant with Kawasaki disease.

J Hum Genet 2021 May 26;66(5):475-489. Epub 2020 Oct 26.

Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan.

In a meta-analysis of three GWAS for susceptibility to Kawasaki disease (KD) conducted in Japan, Korea, and Taiwan and follow-up studies with a total of 11,265 subjects (3428 cases and 7837 controls), a significantly associated SNV in the immunoglobulin heavy variable gene (IGHV) cluster in 14q33.32 was identified (rs4774175; OR = 1.20, P = 6.0 × 10). Investigation of nonsynonymous SNVs of the IGHV cluster in 9335 Japanese subjects identified the C allele of rs6423677, located in IGHV3-66, as the most significant reproducible association (OR = 1.25, P = 6.8 × 10 in 3603 cases and 5731 controls). We observed highly skewed allelic usage of IGHV3-66, wherein the rs6423677 A allele was nearly abolished in the transcripts in peripheral blood mononuclear cells of both KD patients and healthy adults. Association of the high-expression allele with KD strongly indicates some active roles of B-cells or endogenous immunoglobulins in the disease pathogenesis. Considering that significant association of SNVs in the IGHV region with disease susceptibility was previously known only for rheumatic heart disease (RHD), a complication of acute rheumatic fever (ARF), these observations suggest that common B-cell related mechanisms may mediate the symptomology of KD and ARF as well as RHD.
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http://dx.doi.org/10.1038/s10038-020-00864-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7585995PMC
May 2021

Identification of type 2 diabetes loci in 433,540 East Asian individuals.

Nature 2020 06 6;582(7811):240-245. Epub 2020 May 6.

Vanderbilt Genetics Institute, Division of Genetic Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.

Meta-analyses of genome-wide association studies (GWAS) have identified more than 240 loci that are associated with type 2 diabetes (T2D); however, most of these loci have been identified in analyses of individuals with European ancestry. Here, to examine T2D risk in East Asian individuals, we carried out a meta-analysis of GWAS data from 77,418 individuals with T2D and 356,122 healthy control individuals. In the main analysis, we identified 301 distinct association signals at 183 loci, and across T2D association models with and without consideration of body mass index and sex, we identified 61 loci that are newly implicated in predisposition to T2D. Common variants associated with T2D in both East Asian and European populations exhibited strongly correlated effect sizes. Previously undescribed associations include signals in or near GDAP1, PTF1A, SIX3, ALDH2, a microRNA cluster, and genes that affect the differentiation of muscle and adipose cells. At another locus, expression quantitative trait loci at two overlapping T2D signals affect two genes-NKX6-3 and ANK1-in different tissues. Association studies in diverse populations identify additional loci and elucidate disease-associated genes, biology, and pathways.
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http://dx.doi.org/10.1038/s41586-020-2263-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7292783PMC
June 2020

Both IgM and IgG Antibodies Against Polyethylene Glycol Can Alter the Biological Activity of Methoxy Polyethylene Glycol-Epoetin Beta in Mice.

Pharmaceutics 2019 Dec 21;12(1). Epub 2019 Dec 21.

Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan.

Pre-existing antibodies that bind polyethylene glycol are present in about 40% of healthy individuals. It is currently unknown if pre-existing anti-polyethylene glycol (PEG) antibodies can alter the bioactivity of pegylated drugs with a single long PEG chain, which represents the majority of newly developed pegylated medicines. Methoxy polyethylene glycol-epoetin beta (PEG-EPO) contains a single 30 kDa PEG chain and is used to treat patients suffering from anemia. We find that the pre-existing human anti-PEG IgM and IgG antibodies from normal donors can bind to PEG-EPO. The prevalence and concentrations of anti-PEG IgM and IgG antibodies were also higher in patients that responded poorly to PEG-EPO. Monoclonal anti-PEG IgM and IgG antibodies at concentrations found in normal donors blocked the biological activity of PEG-EPO to stimulate the production of new erythrocytes in mice and accelerated the clearance of I-PEG-EPO, resulting in PEG-EPO accumulation primarily in the liver and spleen. Accelerated clearance by the anti-PEG IgG antibody was mediated by the Fc portion of the antibody. Importantly, infusing higher doses of PEG-EPO could compensate for the inhibitory effects of anti-PEG antibodies, suggesting that pre-existing anti-PEG antibodies can be "dosed through." Our study indicates that the bioactivity and therapeutic activity of PEG-EPO may be reduced in patients with elevated levels of pre-existing anti-PEG antibodies. New pegylated medicines with a single long PEG chain may also be affected in patients with high levels of anti-PEG antibodies.
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http://dx.doi.org/10.3390/pharmaceutics12010015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7022322PMC
December 2019

Palmitoyl Acyltransferase Activity of ZDHHC13 Regulates Skin Barrier Development Partly by Controlling PADi3 and TGM1 Protein Stability.

J Invest Dermatol 2020 05 25;140(5):959-970.e3. Epub 2019 Oct 25.

Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan; Taiwan Mouse Clinic, Academia Sinica, Taipei, Taiwan. Electronic address:

Deficiency of the palmitoyl-acyl transferase ZDHHC13 compromises skin barrier permeability and renders mice susceptible to environmental bacterial infection and inflammatory dermatitis. It had been unclear how the lack of ZDHHC13 proteins resulted in cutaneous abnormalities. In this study, we first demonstrate that enzymatic palmitoylation activity, rather than protein scaffolding, by ZDHHC13 is essential for skin barrier integrity, showing that knock-in mice bearing an enzymatically dead DQ-to-AA ZDHHC13 mutation lost their hair after weaning cyclically, recapitulating knockout phenotypes of skin inflammation and dermatitis. To establish the ZDHHC13 substrates responsible for skin barrier development, we employed quantitative proteomic approaches to identify protein molecules whose palmitoylation is tightly controlled by ZDHHC13. We identified over 300 candidate proteins that could be classified into four biological categories: immunological disease, skin development and function, dermatological disease, and lipid metabolism. Palmitoylation of three of these candidates-loricrin, peptidyl arginine deiminase type III, and keratin fiber crosslinker transglutaminase 1-by ZDHHC13 was confirmed by biochemical assay. Palmitoylation was critical for in vivo protein stability of the latter two candidates. Our findings reveal the importance of protein palmitoylation in skin barrier development, partly by promoting envelope protein crosslinking and the filaggrin processing pathway.
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http://dx.doi.org/10.1016/j.jid.2019.09.017DOI Listing
May 2020

Genome-wide transcriptome analysis to further understand neutrophil activation and lncRNA transcript profiles in Kawasaki disease.

Sci Rep 2019 01 23;9(1):328. Epub 2019 Jan 23.

Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.

Kawasaki disease (KD) is the most common cause of acquired cardiac disease in children in developed countries. However, little is known regarding the role of transcriptomic targets of KD in the disease progression and development of complications, especially coronary artery aneurysms (CAA). The aim of our study was to identify transcripts affected by KD and their potential role in the disease. We enrolled 37 KD patients and collected blood samples along a comprehensive time-course. mRNA profiling demonstrated an abundance of CD177 transcript in acute KD, and in the intravenous immunoglobulin (IVIG)-resistant group compared to in the IVIG-sensitive group. lncRNA profiling identified XLOC_006277 as the most highly expressed molecule. XLOC_006277 expression in patients at acute stage was 3.3-fold higher relative to patients with convalescent KD. Moreover, XLOC_006277 abundance increased significantly in patients with CAA. XLOC_006277 knockdown suppressed MMP-8 and MMP-9 expression, both associated with heart lesions. Our result suggested that the increase of CD177 neutrophils was associated with KD. Moreover, this study provided global long non-coding RNA transcripts in the blood of patients with KD, IVIG-resistant KD, or CAA. Notably, XLOC_006277 abundance was associated with CAA, which might contribute to further understanding of CAA pathogenesis in KD.
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http://dx.doi.org/10.1038/s41598-018-36520-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6344526PMC
January 2019

Interethnic analyses of blood pressure loci in populations of East Asian and European descent.

Nat Commun 2018 11 28;9(1):5052. Epub 2018 Nov 28.

Tohoku Medical Megabank Organization, Tohoku University, Sendai, 980-8573, Japan.

Blood pressure (BP) is a major risk factor for cardiovascular disease and more than 200 genetic loci associated with BP are known. Here, we perform a multi-stage genome-wide association study for BP (max N = 289,038) principally in East Asians and meta-analysis in East Asians and Europeans. We report 19 new genetic loci and ancestry-specific BP variants, conforming to a common ancestry-specific variant association model. At 10 unique loci, distinct non-rare ancestry-specific variants colocalize within the same linkage disequilibrium block despite the significantly discordant effects for the proxy shared variants between the ethnic groups. The genome-wide transethnic correlation of causal-variant effect-sizes is 0.898 and 0.851 for systolic and diastolic BP, respectively. Some of the ancestry-specific association signals are also influenced by a selective sweep. Our results provide new evidence for the role of common ancestry-specific variants and natural selection in ethnic differences in complex traits such as BP.
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http://dx.doi.org/10.1038/s41467-018-07345-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6261994PMC
November 2018

Immunoglobulin profiling identifies unique signatures in patients with Kawasaki disease during intravenous immunoglobulin treatment.

Hum Mol Genet 2018 08;27(15):2671-2677

Department of Medicine, University of Chicago, Chicago, Illinois, USA.

Identifying the causes of high fever syndromes such as Kawasaki disease (KD) remains challenging. To investigate pathogen exposure signatures in suspected pathogen-mediated diseases such as KD, we performed immunoglobulin (Ig) profiling using a next-generation sequencing method. After intravenous Ig (IVIG) treatment, we observed disappearance of clonally expanded IgM clonotypes, which were dominantly observed in acute-phase patients. The complementary-determining region 3 (CDR3) sequences of dominant IgM clonotypes in acute-phase patients were commonly observed in other Ig isotypes. In acute-phase KD patients, we identified 32 unique IgM CDR3 clonotypes shared in three or more cases. Furthermore, before the IVIG treatment, the sums of dominant IgM clonotypes in IVIG-resistant KD patients were significantly higher than those of IVIG-sensitive KD patients. Collectively, we demonstrate a novel approach for identifying certain Ig clonotypes for potentially interacting with pathogens involved in KD; this approach could be applied for a wide variety of fever-causing diseases of unknown origin.
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http://dx.doi.org/10.1093/hmg/ddy176DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6048982PMC
August 2018

Clinical Pharmacogenetics Implementation Consortium Guideline for HLA Genotype and Use of Carbamazepine and Oxcarbazepine: 2017 Update.

Clin Pharmacol Ther 2018 04 2;103(4):574-581. Epub 2018 Feb 2.

Department of Pharmacology, University of Liverpool, Liverpool, UK.

The variant allele HLA-B*15:02 is strongly associated with greater risk of Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) in patients treated with carbamazepine or oxcarbazepine. The variant allele HLA-A*31:01 is associated with greater risk of maculopapular exanthema, drug reaction with eosinophilia and systemic symptoms, and SJS/TEN in patients treated with carbamazepine. We summarize evidence from the published literature supporting these associations and provide recommendations for carbamazepine and oxcarbazepine use based on HLA genotypes.
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http://dx.doi.org/10.1002/cpt.1004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5847474PMC
April 2018

Loss of GPNMB Causes Autosomal-Recessive Amyloidosis Cutis Dyschromica in Humans.

Am J Hum Genet 2018 02 11;102(2):219-232. Epub 2018 Jan 11.

Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan. Electronic address:

Amyloidosis cutis dyschromica (ACD) is a distinct form of primary cutaneous amyloidosis characterized by generalized hyperpigmentation mottled with small hypopigmented macules on the trunks and limbs. Affected families and sporadic case subjects have been reported predominantly in East and Southeast Asian ethnicities; however, the genetic cause has not been elucidated. We report here that the compound heterozygosity or homozygosity of GPNMB truncating alleles is the cause of autosomal-recessive ACD. Six nonsense or frameshift mutations were identified in nine individuals diagnosed with ACD. Immunofluorescence analysis of skin biopsies showed that GPNMB is expressed in all epidermal cells, with the highest staining observed in melanocytes. GPNMB staining is significantly reduced in the lesional skin of affected individuals. Hyperpigmented lesions exhibited significantly increased amounts of DNA/keratin-positive amyloid deposits in the papillary dermis and infiltrating macrophages compared with hypo- or depigmented macules. Depigmentation of the lesions was attributable to loss of melanocytes. Intracytoplasmic fibrillary aggregates were observed in keratinocytes scattered in the lesional epidermis. Thus, our analysis indicates that loss of GPNMB, which has been implicated in melanosome formation, autophagy, phagocytosis, tissue repair, and negative regulation of inflammation, underlies autosomal-recessive ACD and provides insights into the etiology of amyloidosis and pigment dyschromia.
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http://dx.doi.org/10.1016/j.ajhg.2017.12.012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5985536PMC
February 2018

A genome-wide association study links small-vessel ischemic stroke to autophagy.

Sci Rep 2017 11 9;7(1):15229. Epub 2017 Nov 9.

Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.

Genome-wide association studies (GWAS) can serve as strong evidence in correlating biological pathways with human diseases. Although ischemic stroke has been found to be associated with many biological pathways, the genetic mechanism of ischemic stroke is still unclear. Here, we performed GWAS for a major subtype of stroke-small-vessel occlusion (SVO)-to identify potential genetic factors contributing to ischemic stroke. GWAS were conducted on 342 individuals with SVO stroke and 1,731 controls from a Han Chinese population residing in Taiwan. The study was replicated in an independent Han Chinese population comprising an additional 188 SVO stroke cases and 1,265 controls. Three SNPs (rs2594966, rs2594973, rs4684776) clustered at 3p25.3 in ATG7 (encoding Autophagy Related 7), with P values between 2.52 × 10 and 3.59 × 10, were identified. Imputation analysis also supported the association between ATG7 and SVO stroke. To our knowledge, this is the first GWAS to link stroke and autophagy. ATG7, which has been implicated in autophagy, could provide novel insights into the genetic basis of ischemic stroke.
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http://dx.doi.org/10.1038/s41598-017-14355-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5680343PMC
November 2017

Identification of functional single nucleotide polymorphisms in the branchpoint site.

Hum Genomics 2017 Nov 9;11(1):27. Epub 2017 Nov 9.

Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.

Background: The human genome contains millions of single nucleotide polymorphisms (SNPs); many of these SNPs are intronic and have unknown functional significance. SNPs occurring within intron branchpoint sites, especially at the adenine (A), would presumably affect splicing; however, this has not been systematically studied. We employed a splicing prediction tool to identify human intron branchpoint sites and screened dbSNP for identifying SNPs located in the predicted sites to generate a genome-wide branchpoint site SNP database.

Results: We identified 600 SNPs located within branchpoint sites; among which, 216 showed a change in A. After scoring the SNPs by counting the As in the ± 10 nucleotide region, only four SNPs were identified without additional As (rs13296170, rs12769205, rs75434223, and rs67785924). Using minigene constructs, we examined the effects of these SNPs on splicing. The three SNPs (rs13296170, rs12769205, and rs75434223) with nucleotide substitution at the A position resulted in abnormal splicing (exon skipping and/or intron inclusion). However, rs67785924, a 5-bp deletion that abolished the branchpoint A nucleotide, exhibited normal RNA splicing pattern, presumably using two of the downstream As as alternative branchpoints. The influence of additional As on splicing was further confirmed by studying rs2733532, which contains three additional As in the ± 10 nucleotide region.

Conclusions: We generated a high-confidence genome-wide branchpoint site SNP database, experimentally verified the importance of A in the branchpoint, and suggested that other nearby As can protect branchpoint A substitution from abnormal splicing.
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http://dx.doi.org/10.1186/s40246-017-0122-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5680774PMC
November 2017

Genome-wide association study identifies novel susceptibility loci for migraine in Han Chinese resided in Taiwan.

Cephalalgia 2018 03 17;38(3):466-475. Epub 2017 Feb 17.

1 Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan.

Background Susceptibility genes for migraine, despite it being a highly prevalent and disabling neurological disorder, have not been analyzed in Asians by genome-wide association study (GWAS). Methods We conducted a two-stage case-control GWAS to identify susceptibility genes for migraine without aura in Han Chinese residing in Taiwan. In the discovery stage, we genotyped 1005 clinic-based Taiwanese migraine patients and 1053 population-based sex-matched controls using Axiom Genome-Wide CHB Array. In the replication stage, we genotyped 27 single-nucleotide polymorphisms with p < 10 in 1120 clinic-based migraine patients and 604 sex-matched normal controls by using Sequenom. Variants at LRP1, TRPM8, and PRDM, which have been replicated in Caucasians, were also genotyped. Results We identified a novel susceptibility locus (rs655484 in DLG2) that reached GWAS significance level for migraine risk in Han Chinese ( p = 1.45 × 10, odds ratio [OR] = 2.42), and also another locus (rs3781545in GFRA1) with suggestive significance ( p = 1.27 × 10, OR = 1.38). In addition, we observed positive association signals with a similar trend to the associations identified in Caucasian GWASs for rs10166942 in TRPM8 (OR = 1.33, 95% confidence interval [CI] = 1.14-1.54, P = 9.99 × 10; risk allele: T) and rs1172113 in LRP1 (OR = 1.23, 95% CI = 1.04-1.45, P = 2.9 × 10; risk allele: T). Conclusion The present study is the first migraine GWAS conducted in Han-Chinese and Asians. The newly identified susceptibility genes have potential implications in migraine pathogenesis. DLG2 is involved in glutamatergic neurotransmission, and GFRA1 encodes GDNF receptors that are abundant in CGRP-containing trigeminal neurons. Furthermore, positive association signals for TRPM8 and LRP1 suggest the possibility for common genetic contributions across ethnicities.
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http://dx.doi.org/10.1177/0333102417695105DOI Listing
March 2018

A genome-wide association study identifies a novel susceptibility locus for the immunogenicity of polyethylene glycol.

Nat Commun 2017 09 12;8(1):522. Epub 2017 Sep 12.

Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan.

Conjugation of polyethylene glycol (PEG) to therapeutic molecules can improve bioavailability and therapeutic efficacy. However, some healthy individuals have pre-existing anti-PEG antibodies and certain patients develop anti-PEG antibody during treatment with PEGylated medicines, suggesting that genetics might play a role in PEG immunogenicity. Here we perform genome-wide association studies for anti-PEG IgM and IgG responses in Han Chinese with 177 and 140 individuals, defined as positive for anti-PEG IgM and IgG responses, respectively, and with 492 subjects without either anti-PEG IgM or IgG as controls. We validate the association results in the replication cohort, consisting of 211 and 192 subjects with anti-PEG IgM and anti-PEG IgG, respectively, and 596 controls. We identify the immunoglobulin heavy chain (IGH) locus to be associated with anti-PEG IgM response at genome-wide significance (P = 2.23 × 10). Our findings may provide novel genetic markers for predicting the immunogenicity of PEG and efficacy of PEGylated therapeutics.Some individuals develop antibodies against the polyethylene glycol that is commonly used in therapeutic preparations. Here the authors conduct a GWAS in Han Chinese and find the IGH locus is associated with anti-PEG IgM.
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http://dx.doi.org/10.1038/s41467-017-00622-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5595925PMC
September 2017

Role of S-Palmitoylation by ZDHHC13 in Mitochondrial function and Metabolism in Liver.

Sci Rep 2017 05 19;7(1):2182. Epub 2017 May 19.

Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.

Palmitoyltransferase (PAT) catalyses protein S-palmitoylation which adds 16-carbon palmitate to specific cysteines and contributes to various biological functions. We previously reported that in mice, deficiency of Zdhhc13, a member of the PAT family, causes severe phenotypes including amyloidosis, alopecia, and osteoporosis. Here, we show that Zdhhc13 deficiency results in abnormal liver function, lipid abnormalities, and hypermetabolism. To elucidate the molecular mechanisms underlying these disease phenotypes, we applied a site-specific quantitative approach integrating an alkylating resin-assisted capture and mass spectrometry-based label-free strategy for studying the liver S-palmitoylome. We identified 2,190 S-palmitoylated peptides corresponding to 883 S-palmitoylated proteins. After normalization using the membrane proteome with TMT10-plex labelling, 400 (31%) of S-palmitoylation sites on 254 proteins were down-regulated in Zdhhc13-deficient mice, representing potential ZDHHC13 substrates. Among these, lipid metabolism and mitochondrial dysfunction proteins were overrepresented. MCAT and CTNND1 were confirmed to be specific ZDHHC13 substrates. Furthermore, we found impaired mitochondrial function in hepatocytes of Zdhhc13-deficient mice and Zdhhc13-knockdown Hep1-6 cells. These results indicate that ZDHHC13 is an important regulator of mitochondrial activity. Collectively, our study allows for a systematic view of S-palmitoylation for identification of ZDHHC13 substrates and demonstrates the role of ZDHHC13 in mitochondrial function and metabolism in liver.
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http://dx.doi.org/10.1038/s41598-017-02159-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5438363PMC
May 2017

Genetic epidemiological study doesn't support GLA IVS4+919G>A variant is a significant mutation in Fabry disease.

Mol Genet Metab 2017 05 24;121(1):22-27. Epub 2017 Mar 24.

Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan; Graduate Institute of Chinese Medical Science, China Medical University, Taichung, Taiwan. Electronic address:

Background: The GLA IVS4+919G>A which is linked to late-onset Fabry disease shows high frequency in Taiwan.

Methods: To determine whether IVS4+919G>A is a frequent cause of heart disease, we genotyped it in normal controls and other disease cohorts (type 2 diabetes, heart failure, ventricular tachycardia, atrial fibrillation and coronary artery disease). Normal controls and diabetes patients carrying the variant were evaluated for their cardiac condition. Minigene constructs were used to study GLA splicing patterns in different cell lines.

Results: GLA IVS4+919A was found in 4/1634 males (0.245%) and 2/1634 females (0.123%) in normal controls and in 4/2133 males (0.188%) and 7/1816 females (0.385%) in the type 2 diabetes cohort. Of all the 17 IVS4+919A carriers in these two groups, only two males reported heart-related disease (myocardial infarction and hypertensive heart disease). Furthermore, in the heart disease cohort (n=649), only one male carried the variant. Minigene constructs showed that the AGS (stomach) cell line showed a distinct GLA splicing pattern.

Conclusion: Most subjects carrying GLA IVS4+919A did not show abnormal cardiac phenotypes. The near-absence of GLA IVS4+919A in heart disease cohort suggested that this variant is not a frequent cause of overt heart diseases in Taiwan and that the genotype-phenotype correlation and natural course of the disease need further investigation. We also showed that the GLA IVS4+919G>A nucleotide change did influence alternative splicing in a tissue-specific manner.

Synopsis: The GLA IVS4+919G>A variant is not a frequent cause of overt heart disease in Taiwan.
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http://dx.doi.org/10.1016/j.ymgme.2017.03.005DOI Listing
May 2017

Association analyses of East Asian individuals and trans-ancestry analyses with European individuals reveal new loci associated with cholesterol and triglyceride levels.

Hum Mol Genet 2017 05;26(9):1770-1784

Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.

Large-scale meta-analyses of genome-wide association studies (GWAS) have identified >175 loci associated with fasting cholesterol levels, including total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG). With differences in linkage disequilibrium (LD) structure and allele frequencies between ancestry groups, studies in additional large samples may detect new associations. We conducted staged GWAS meta-analyses in up to 69,414 East Asian individuals from 24 studies with participants from Japan, the Philippines, Korea, China, Singapore, and Taiwan. These meta-analyses identified (P < 5 × 10-8) three novel loci associated with HDL-C near CD163-APOBEC1 (P = 7.4 × 10-9), NCOA2 (P = 1.6 × 10-8), and NID2-PTGDR (P = 4.2 × 10-8), and one novel locus associated with TG near WDR11-FGFR2 (P = 2.7 × 10-10). Conditional analyses identified a second signal near CD163-APOBEC1. We then combined results from the East Asian meta-analysis with association results from up to 187,365 European individuals from the Global Lipids Genetics Consortium in a trans-ancestry meta-analysis. This analysis identified (log10Bayes Factor ≥6.1) eight additional novel lipid loci. Among the twelve total loci identified, the index variants at eight loci have demonstrated at least nominal significance with other metabolic traits in prior studies, and two loci exhibited coincident eQTLs (P < 1 × 10-5) in subcutaneous adipose tissue for BPTF and PDGFC. Taken together, these analyses identified multiple novel lipid loci, providing new potential therapeutic targets.
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http://dx.doi.org/10.1093/hmg/ddx062DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6075203PMC
May 2017

Knock-in human FGFR3 achondroplasia mutation as a mouse model for human skeletal dysplasia.

Sci Rep 2017 02 23;7:43220. Epub 2017 Feb 23.

Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan.

Achondroplasia (ACH), the most common genetic dwarfism in human, is caused by a gain-of function mutation in fibroblast growth factor receptor 3 (FGFR3). Currently, there is no effective treatment for ACH. The development of an appropriate human-relevant model is important for testing potential therapeutic interventions before human clinical trials. Here, we have generated an ACH mouse model in which the endogenous mouse Fgfr3 gene was replaced with human FGFR3 (FGFR3) cDNA, the most common mutation in human ACH. Heterozygous (FGFR3) and homozygous (FGFR3) mice expressing human FGFR3 recapitulate the phenotypes observed in ACH patients, including growth retardation, disproportionate shortening of the limbs, round head, mid-face hypoplasia at birth, and kyphosis progression during postnatal development. We also observed premature fusion of the cranial sutures and low bone density in newborn FGFR3 mice. The severity of the disease phenotypes corresponds to the copy number of activated FGFR3, and the phenotypes become more pronounced during postnatal skeletal development. This mouse model offers a tool for assessing potential therapeutic approaches for skeletal dysplasias related to over-activation of human FGFR3, and for further studies of the underlying molecular mechanisms.
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http://dx.doi.org/10.1038/srep43220DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5322349PMC
February 2017

Filamin B Loss-of-Function Mutation in Dimerization Domain Causes Autosomal-Recessive Spondylocarpotarsal Synostosis Syndrome with Rib Anomalies.

Hum Mutat 2017 05 27;38(5):540-547. Epub 2017 Feb 27.

Department of Medical Genetics, China Medical University Hospital, Taichung, Taiwan.

Spondylocarpotarsal synostosis syndrome (SCT) is a distinct group of disorders characterized by short stature, disrupted vertebral segmentation with vertebral fusion, scoliosis, lordosis, carpal/tarsal synostosis, and lack of rib anomalies. Mutations in filamin B (FLNB) and MYH3 have been reported for autosomal-recessive and autosomal-dominant SCT, respectively. We present a family with two patients suffering from autosomal-recessive SCT with rib anomalies, including malalignment, crowding, and uneven size and shape of ribs. Whole-exome sequencing revealed a novel p.S2542Lfs 82 (c.7621dup) frameshift mutation in FLNB. This frameshift mutation lies in the C-terminal-most domain involved in FLNB dimerization and resulted in a 20-residue elongation, with complete familial segregation and absence in 376 normal controls. The mutant p.S2542Lfs 82 FLNB demonstrated a complete loss of ability to form a functional dimer in transiently transfected HEK293T cells. The p.S2542Lfs 82 mutation also led to significantly reduced protein levels and accumulation of the mutant protein in the Golgi apparatus. This is the first identified mutation in the dimerization domain of FLNB. This loss-of-function frameshift mutation in FLNB causes autosomal-recessive SCT with rarely reported rib anomalies. This report demonstrates the involvement of rib anomaly in SCT and its causative mutation in the dimerization domain of FLNB.
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http://dx.doi.org/10.1002/humu.23186DOI Listing
May 2017

Pharmacogenetic dosing of warfarin in the Han-Chinese population: a randomized trial.

Pharmacogenomics 2017 Feb 23;18(3):245-253. Epub 2017 Jan 23.

Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.

Aim: This study aimed to determine clinical utility of genotype-guided dosing for warfarin in Han-Chinese.

Methods: A total of 320 patients were randomly assigned International Warfarin Pharmacogenetic Consortium algorithm, Taiwan algorithm and optimal clinical care arms. The primary outcome of the study was the percentage of time in the therapeutic range during the first 90 days of treatment.

Results: The percentage of time in the therapeutic range of the clinical care group in the first 2 weeks was significantly higher than the algorithm groups. This difference was no longer observed after 4 weeks. No difference in excessive anticoagulation (international normalized ratio ≥4.0) and adverse events was observed.

Conclusion: Genotype-guided dosing did not provide significant benefit. Loading dose with frequent international normalized ratio monitoring could provide sufficient control of anticoagulation.
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http://dx.doi.org/10.2217/pgs-2016-0154DOI Listing
February 2017

Protein Palmitoylation by ZDHHC13 Protects Skin against Microbial-Driven Dermatitis.

J Invest Dermatol 2017 04 23;137(4):894-904. Epub 2016 Dec 23.

Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan; Taiwan Mouse Clinic, Academia Sinica, Taipei, Taiwan. Electronic address:

Atopic dermatitis is a complex chronic inflammatory skin disorder that results from intimate interactions among genetic predisposition, host environment, skin barrier defects, and immunological factors. However, a clear genetic roadmap leading to atopic dermatitis remains to be fully explored. From a genome-wide mutagenesis screen, deficiency of ZDHHC13, a palmitoylacyl transferase, has previously been associated with skin and multitissue inflammatory phenotypes. Here, we report that ZDHHC13 is required for skin barrier integrity and that deficiency of ZDHHC13 renders mice susceptible to environmental bacteria, resulting in persistent skin inflammation and an atopic dermatitis-like disease. This phenotype is ameliorated in a germ-free environment and is also attenuated by antibiotic treatment, but not by deletion of the Rag1 gene, suggesting that a microbial factor triggers inflammation rather than intrinsic adaptive immunity. Furthermore, skin from ZDHHC13-deficient mice has both elevated levels of IL-33 and type 2 innate lymphoid cells, reinforcing the role of innate immunity in the development of atopic dermatitis. In summary, our study suggests that loss of ZDHHC13 in skin impairs the integrity of multiple barrier functions and leads to a dermatitis lesion in response to microbial encounters.
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http://dx.doi.org/10.1016/j.jid.2016.12.011DOI Listing
April 2017

Genome-wide Trans-ethnic Meta-analysis Identifies Seven Genetic Loci Influencing Erythrocyte Traits and a Role for RBPMS in Erythropoiesis.

Am J Hum Genet 2017 Jan 22;100(1):51-63. Epub 2016 Dec 22.

Icahn Institute for Multiscale Biology, Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.

Genome-wide association studies (GWASs) have identified loci for erythrocyte traits in primarily European ancestry populations. We conducted GWAS meta-analyses of six erythrocyte traits in 71,638 individuals from European, East Asian, and African ancestries using a Bayesian approach to account for heterogeneity in allelic effects and variation in the structure of linkage disequilibrium between ethnicities. We identified seven loci for erythrocyte traits including a locus (RBPMS/GTF2E2) associated with mean corpuscular hemoglobin and mean corpuscular volume. Statistical fine-mapping at this locus pointed to RBPMS at this locus and excluded nearby GTF2E2. Using zebrafish morpholino to evaluate loss of function, we observed a strong in vivo erythropoietic effect for RBPMS but not for GTF2E2, supporting the statistical fine-mapping at this locus and demonstrating that RBPMS is a regulator of erythropoiesis. Our findings show the utility of trans-ethnic GWASs for discovery and characterization of genetic loci influencing hematologic traits.
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http://dx.doi.org/10.1016/j.ajhg.2016.11.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5223059PMC
January 2017

Correlations between the enantio- and regio-selective metabolisms of warfarin.

Pharmacogenomics 2017 Jan 20;18(2):133-142. Epub 2016 Dec 20.

Department of Pharmacotherapy, Meiji Pharmaceutical University, Tokyo, Japan.

Aim: To clarify whether the activities of multiple CYPs associated with warfarin metabolism would be correlated with each other.

Methods: Oral clearances (CLpo) of warfarin enantiomers were estimated in 378 Chinese, Caucasians and African-Americans. The partial metabolic clearances (CLm) for 7-hydroxywarfarin enantiomers were also measured. In addition, CLpo and CLm were determined in a patient on warfarin and rifampicin.

Results: Correlations between CLpo for warfarin enantiomers existed across the three populations. In addition, there was a significant correlation between the CLm for 7-hydroxylation of warfarin enantiomers. Under induced conditions by rifampicin, there were significant correlations between the enantio- and regio-selective metabolisms of warfarin.

Conclusion: Metabolic activities of CYP2C9, CYP1A2 and CYP3A4 may be regulated by common transcriptional mechanism(s).
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http://dx.doi.org/10.2217/pgs-2016-0149DOI Listing
January 2017

Measurement of Pre-Existing IgG and IgM Antibodies against Polyethylene Glycol in Healthy Individuals.

Anal Chem 2016 11 21;88(21):10661-10666. Epub 2016 Oct 21.

Institute of Biomedical Sciences, Academia Sinica , Taipei 11529, Taiwan.

Polyethylene glycol (PEG) is a biocompatible polymer that is often attached to therapeutic molecules to improve bioavailability and therapeutic efficacy. Although antibodies with specificity for PEG may compromise the safety and effectiveness of PEGylated medicines, the prevalence of pre-existing anti-PEG antibodies in healthy individuals is unclear. Chimeric human anti-PEG antibody standards were created to accurately measure anti-PEG IgM and IgG antibodies by direct ELISA with confirmation by a competition assay in the plasma of 1504 healthy Han Chinese donors residing in Taiwan. Anti-PEG antibodies were detected in 44.3% of healthy donors with a high prevalence of both anti-PEG IgM (27.1%) and anti-PEG IgG (25.7%). Anti-PEG IgM and IgG antibodies were significantly more common in females as compared to males (32.0% vs 22.2% for IgM, p < 0.0001 and 28.3% vs 23.0% for IgG, p = 0.018). The prevalence of anti-PEG IgG antibodies was higher in younger (up to 60% for 20 year olds) as opposed to older (20% for >50 years) male and female donors. Anti-PEG IgG concentrations were negatively associated with donor age in both females (p = 0.0073) and males (p = 0.026). Both anti-PEG IgM and IgG strongly bound PEGylated medicines. The described assay can assist in the elucidation of the impact of anti-PEG antibodies on the safety and therapeutic efficacy of PEGylated medicines.
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http://dx.doi.org/10.1021/acs.analchem.6b03109DOI Listing
November 2016

Population structure of Han Chinese in the modern Taiwanese population based on 10,000 participants in the Taiwan Biobank project.

Hum Mol Genet 2016 12;25(24):5321-5331

Taiwan Biobank, Academia Sinica, Taipei City, Taiwan.

The Taiwan Biobank (TWB) aims to build a nationwide research database that integrates genomic/epigenomic profiles, lifestyle patterns, dietary habits, environmental exposure history and long-term health outcomes of 300,000 residents of Taiwan. We describe here an investigation of the population structure of Han Chinese on this Pacific island using genotype data of 591,048 SNPs in an initial freeze of 10,801 unrelated TWB participants. In addition to the North-South cline reported in other Han Chinese populations, we find the Taiwanese Han Chinese clustered into three cline groups: 5% were of northern Han Chinese ancestry, 79.9% were of southern Han Chinese ancestry, and 14.5% belonged to a third (T) group. We also find that this T group is genetically distinct from neighbouring Southeast Asians and Austronesian tribes but similar to other southern Han Chinese. Interestingly, high degree of LD between HLA haplotype A*33:03-B*58:01, an MHC allele being of pathological relevance, and SNPs across the MHC region was observed in subjects with T origin, but not in other Han Chinese. This suggested the T group individuals may have experienced evolutionary events independent from the other southern Han Chinese. Based on the newly-discovered population structure, we detect different loci susceptible to type II diabetes in individuals with southern and northern Han Chinese ancestries. Finally, as one of the largest dataset currently available for the Chinese population, genome-wide statistics for the 10,810 subjects are made publicly accessible through Taiwan View (https://taiwanview.twbiobank.org.tw/index; date last accessed October 14, 2016) to encourage future genetic research and collaborations with the island Taiwan.
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http://dx.doi.org/10.1093/hmg/ddw346DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6078601PMC
December 2016

Identification of susceptibility gene associated with female primary Sjögren's syndrome in Han Chinese by genome-wide association study.

Hum Genet 2016 Nov 8;135(11):1287-1294. Epub 2016 Aug 8.

National Center for Genome Medicine, Institute of Biomedical Sciences, Academia Sinica, 128 Sec. 2, Academia Rd. Nankang, Taipei, 11529, Taiwan.

Primary Sjögren's syndrome (PSS) is an autoimmune disease targeting exocrine glands. It ten times more dominantly affects women than men with an onset peak at menopause. The genetic factor predisposing women to PSS remains unclear. Therefore, we aimed to identify susceptibility loci for PSS in women. We performed genome-wide association study (GWAS) using 242 female PSS patients and 1444 female control in Han Chinese population residing in Taiwan. Replication was conducted in an independent cohort of 178 female PSS and 14,432 control subjects. We identified rs117026326 on GTF2I with GWAS significance (P = 1.10 × 10) and rs13079920 on RBMS3 with suggestive significance (P = 2.90 × 10) associating with PSS in women. The association of RBMS3 was further evidenced by imputation in which rs13072846 (P = 4.89 × 10) was identified and confirmed as female PSS associating SNP within the same LD with rs13079920. PSS pathogenesis involves both immune (effector) and exocrine (target) system. We suggested that while GTF2I is a previously reported associating gene which may function in immune system, RBMS3 is a novel susceptibility gene that predisposes women to PSS potentially through modulating acinar apoptosis and TGF-β signaling in target exocrine system.
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http://dx.doi.org/10.1007/s00439-016-1716-0DOI Listing
November 2016

Homozygosity Mapping and Whole-Genome Sequencing Links a Missense Mutation in POMGNT1 to Autosomal Recessive Retinitis Pigmentosa.

Invest Ophthalmol Vis Sci 2016 Jul;57(8):3601-9

Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.

Purpose: To identify the genetic cause in five families with autosomal recessive retinitis pigmentosa, a genetic disorder involving retinal degeneration and visual loss with high genetic heterogeneity.

Methods: We performed whole-genome single nucleotide polymorphism genotyping on 35 members from the five families to map the region of homozygosity shared by all patients. Whole-genome sequencing was then conducted on one of the patients and a novel variant was identified in POMGNT1 from the homozygous region, which was confirmed by Sanger sequencing and sequenced in all family members. Mutant and wild-type POMGNT1 were expressed in heterologous cells to assess enzyme activity.

Results: A 1.8-Mb homozygous region was identified at 1p34-p33 shared by all 17 patients. Whole-genome sequencing revealed a novel missense mutation in POMGNT1 (c.359A>C, p.Leu120Arg) from this homozygous region, which was shown to co-segregate with disease phenotype. The mutant protein carrying this missense mutation showed an approximately 80% decrease in POMGNT1 enzyme activity compared with the wild type.

Conclusions: We identified a novel mutation in POMGNT1 that causes nonsyndromic autosomal recessive retinitis pigmentosa, adding to the genetic heterogeneity of this retinal disease. POMGNT1 encodes a glycosyltransferase in O-mannosyl glycosylation and was previously found to be responsible for a group of congenital muscular dystrophies called dystroglycanopathies. Our discovery suggests the involvement of O-mannosyl glycosylation in retinitis pigmentosa and presents an instance of POMGNT1 mutation that does not involve muscular dystrophy.
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http://dx.doi.org/10.1167/iovs.16-19463DOI Listing
July 2016

Over-expression of AURKA, SKA3 and DSN1 contributes to colorectal adenoma to carcinoma progression.

Oncotarget 2016 Jul;7(29):45803-45818

Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.

Development of colorectal cancer (CRC) involves sequential transformation of normal mucosal tissues into benign adenomas and then adenomas into malignant tumors. The identification of genes crucial for malignant transformation in colorectal adenomas (CRAs) has been based primarily on cross-sectional observations. In this study, we identified relevant genes using autologous samples. By performing genome-wide SNP genotyping and RNA sequencing analysis of adenocarcinomas, adenomatous polyps, and non-neoplastic colon tissues (referred as tri-part samples) from individual patients, we identified 68 genes with differential copy number alterations and progressively dysregulated expression. Aurora A, SKA3, and DSN1 protein levels were sequentially up-regulated in the samples, and this overexpression was associated with chromosome instability (CIN). Knockdown of SKA3 in CRC cells dramatically reduced cell growth rates and increased apoptosis. Depletion of SKA3 or DSN1 induced G2/M arrest and decreased migration, invasion, and anchorage-independent growth. AURKA and DSN1 are thus critical for chromosome 20q amplification-associated malignant transformation in CRA. Moreover, SKA3 at chromosome 13q was identified as a novel gene involved in promoting malignant transformation. Evaluating the expression of these genes may help identify patients with progressive adenomas, helping to improve treatment.
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http://dx.doi.org/10.18632/oncotarget.9960DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5216762PMC
July 2016

Antimicrobial Properties of an Immunomodulator - 15 kDa Human Granulysin.

PLoS One 2016 8;11(6):e0156321. Epub 2016 Jun 8.

Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan.

Granulysin, a cationic protein expressed by human natural killer cells and cytotoxic T lymphocytes, is a mediator for drug-induced Stevens-Johnson syndrome and graft-versus-host disease. Some 15 kDa granulysin are processed into 9 kDa forms and sequestered in cytolytic granules, while others are constitutively secreted into body fluids. Both 9 and 15 kDa granulysin have been shown to be a serum marker for cell-mediated immunity. Furthermore, 15 kDa is able to activate monocyte differentiation. However, its antimicrobial properties have not been clearly addressed. Here, we report a novel method to prepare both the soluble 9 and 15 kDa granulysin and show that the 15 kDa form is more effective than the 9 kDa form in exerting specific antimicrobial activity against Pseudomonas aeruginosa within a range of few micromolars. We also show that the 15 kDa granulysin is able to hyperpolarize the membrane potential and increase membrane permeability of treated bacteria. Interestingly, the bactericidal activity and membrane permeability of the granulysins were markedly reduced at lower pH (pH 5.4) as a result of probable increase in hydrophobicity of the granulysins. Additionally, we've also shown the granulysin to inhibit biofilm formation by P. aeruginosa. These results suggest that the 15 kDa granulysin exhibits a novel mechanism in bacteria killing in a way that's different from most antimicrobial peptides. Our novel granulysin preparation methodology will be useful for further study of action mechanisms of other antimicrobial, cytotoxic and immunomodulating properties in granulysin-mediated diseases.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0156321PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4898823PMC
July 2017

Genome-wide analysis of copy number variations identifies PARK2 as a candidate gene for autism spectrum disorder.

Mol Autism 2016 1;7:23. Epub 2016 Apr 1.

Department of Psychiatry, National Taiwan University Hospital and College of Medicine, No. 7, Chung-Shan South Road, Taipei, 10002 Taiwan.

Background: Autism spectrum disorder (ASD) is an early-onset neurodevelopmental disorder with complex genetic underpinning in its etiology. Copy number variations (CNVs) as one of the genetic factors associated with ASD have been addressed in recent genome-wide association studies (GWAS). However, the significance of CNV has not been well investigated in non-Caucasian ASD population.

Methods: To identify the pathogenic CNVs responsible for ASD in Han Chinese, we performed a segment-based GWAS of CNV in 335 ASD cases and 1093 healthy controls using Affymetrix single nucleotide polymorphism (SNP) array by focusing on case-specific CNVs. PARK2 was one of the important genes with several case-specific regions overlapped on it. The findings were validated in the initial screen sample set and replicated in another sample set by real-time quantitative PCR (qPCR).

Results: A total of six CNVs at 6q26 that spanned different exons of PARK2 were identified. The PARK2 expression level was down-regulated at exon-dependent manner in cases with either deletion or duplication. The result revealed that the gene function might be disrupted by exonic deletion and duplication. We also observed that the ASD case with exonic duplication demonstrated a more severe interference of PARK2 expression and the clinical feature than the ones with deletion at the exons 2-4 of the PARK2 gene.

Conclusions: Our finding provides evidence to support that CNVs affecting PARK2 function might contribute to genetic etiology of a proportion of cases with ASD. The intriguing results of this work warrant further study on characterizing the functional impact of various exonic CNVs on the PARK2 gene.

Trial Registration: ClinicalTrials.gov NCT00494754.
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http://dx.doi.org/10.1186/s13229-016-0087-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4818409PMC
December 2016

An integrated analysis tool for analyzing hybridization intensities and genotypes using new-generation population-optimized human arrays.

BMC Genomics 2016 Mar 31;17:266. Epub 2016 Mar 31.

Bioinformatics Program, Taiwan International Graduate Program, Institute of Information Science, Academia Sinica, Taipei, 115, Taiwan.

Background: Affymetrix Axiom single nucleotide polymorphism (SNP) arrays provide a cost-effective, high-density, and high-throughput genotyping solution for population-optimized analyses. However, no public software is available for the integrated genomic analysis of hybridization intensities and genotypes for this new-generation population-optimized genotyping platform.

Results: A set of statistical methods was developed for an integrated analysis of allele frequency (AF), allelic imbalance (AI), loss of heterozygosity (LOH), long contiguous stretch of homozygosity (LCSH), and copy number variation or alteration (CNV/CNA) on the basis of SNP probe hybridization intensities and genotypes. This study analyzed 3,236 samples that were genotyped using different SNP platforms. The proposed AF adjustment method considerably increased the accuracy of AF estimation. The proposed quick circular binary segmentation algorithm for segmenting copy number reduced the computation time of the original segmentation method by 30-67 %. The proposed CNV/CNA detection, which integrates AI and LOH/LCSH detection, had a promising true positive rate and well-controlled false positive rate in simulation studies. Moreover, our real-time quantitative polymerase chain reaction experiments successfully validated the CNVs/CNAs that were identified in the Axiom data analyses using the proposed methods; some of the validated CNVs/CNAs were not detected in the Affymetrix Array 6.0 data analysis using the Affymetrix Genotyping Console. All the analysis functions are packaged into the ALICE (AF/LOH/LCSH/AI/CNV/CNA Enterprise) software.

Conclusions: ALICE and the used genomic reference databases, which can be downloaded from http://hcyang.stat.sinica.edu.tw/software/ALICE.html , are useful resources for analyzing genomic data from the Axiom and other SNP arrays.
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http://dx.doi.org/10.1186/s12864-016-2478-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4815280PMC
March 2016
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