ABSTRACT
OBJECTIVE@#To explore whether WNT signaling pathway genes were associated with non-syndromic oral clefts (NSOC) based on haplotypes analyses among 1 008 Chinese NSOC case-parent trios.@*METHODS@#The genome-wide association study (GWAS) data of 806 Chinese non-syndromic cleft lip with or without cleft palate (NSCL/P) trios and 202 Chinese non-syndromic cleft palate (NSCP) case-parent trios were drawn from the International Consortium to Identify Genes and Interactions Controlling Oral Clefts (ICOCs) study GWAS data set, whose Chinese study population were recruited from four provinces in China, namely Taiwan, Shandong, Hubei, and Sichuan provinces. The process of DNA genotyping was conducted by the Center for Inherited Disease Research in the Johns Hopkins University, using Illumina Human610-Quad v.1_B Bead Chip. The method of sliding windows was used to determine the haplotypes for analyses, including 2 SNPs haplotypes and 3 SNPs haplotypes. Haplotypes with a frequency lower than 1% were excluded for further analyses. To further assess the association between haplotypes and NSOC risks, and the transmission disequilibrium test (TDT) was performed. The Bonferroni method was adopted to correct multiple tests in the study, with which the threshold of statistical significance level was set as P < 0.05 divided by the number of tests, e.g P < 3.47×10-4 in the current stu-dy. All the statistical analyses were performed by using plink (v1.07).@*RESULTS@#After quality control, a total of 144 single nucleotide polymorphisms (SNPs) mapped in seven genes in WNT signaling pathway were included for the analyses among the 806 Chinese NSCL/P trios and 202 Chinese NSCP trios. A total of 1 042 haplotypes with frequency higher than 1% were included for NSCL/P analyses and another 1 057 haplotypes with frequency higher than 1% were included for NSCP analyses. Results from the TDT analyses showed that a total of 69 haplotypes were nominally associated with the NSCL/P risk among Chinese (P < 0.05). Another 34 haplotypes showed nominal significant association with the NSCP risk among Chinese (P < 0.05). However, none of these haplotypes reached pre-defined statistical significance level after Bonferroni correction (P>3.47×10-4).@*CONCLUSION@#This study failed to observe any statistically significant associations between haplotypes of seven WNT signaling pathway genes and the risk of NSOC among Chinese. Further studies are warranted to replicate the findings here.
Subject(s)
Humans , Cleft Lip/genetics , Cleft Palate/genetics , Genetic Predisposition to Disease , Genome-Wide Association Study , Genotype , Haplotypes , Polymorphism, Single Nucleotide , Wnt Signaling Pathway/geneticsABSTRACT
OBJECTIVE@#In this study, we used genome-wide association study (GWAS) data to explore whether WNT pathway genes were associated with non-syndromic oral clefts (NSOC) considering gene-gene interaction and gene-environment interaction.@*METHODS@#We conducted the analysis using 806 non-syndromic cleft lip with or without cleft palate (NSCL/P) case-parent trios and 202 non-syndromic cleft palate (NSCP) case-parent trios among Chinese populations selected from an international consortium established for a GWAS of non-syndromic oral clefts. Genotype data and maternal environmental exposures were collected through DNA samples and questionnaires. Conditional Logistic regression models were adopted to explore gene-gene interaction and gene-environment in teraction using trio package in R software. The threshold of significance level was set as 3.47×10-4 using Bonferroni correction.@*RESULTS@#A total of 144 single nucleotide polymorphisms (SNPs) in seven genes passed the quality control process in NSCL/P trios and NSCP trios, respectively. Totally six pairs of SNPs interactions showed statistically significant SNP-SNP interaction (P < 3.47×10-4) after Bonferroni correction, which were rs7618735 (WNT5A) and rs10848543 (WNT5B), rs631948 (WNT11) and rs556874 (WNT5A), and rs631948 (WNT11) and rs472631 (WNT5A) among NSCL/P trios; rs589149 (WNT11) and rs4765834 (WNT5B), rs1402704 (WNT11) and rs358792 (WNT5A), and rs1402704 (WNT11) and rs358793 (WNT5A) among NSCP trios, respectively. In addition, no significant result was found for gene-environment interaction analysis in both of the NSCL/P trios and NSCP trios.@*CONCLUSION@#Though this study failed to detect significant association based on gene-environment interactions of seven WNT pathway genes and the risk of NSOC, WNT pathway genes may influence the risk of NSOC through potential gene-gene interaction.
Subject(s)
Humans , Asian People/genetics , Cleft Lip/genetics , Cleft Palate/genetics , Genome-Wide Association Study , Wnt Signaling Pathway/geneticsABSTRACT
Objective@#Non-syndromic cleft lip with or without cleft palate (NSCL/P) is a common birth defect with its genetic evidence widely explored. This study explored the potential the parent-of-origin (PoO) effect of WNT pathway on the risks of NSCL/P, using a case-parent trio design.@*Methods@#Data on the single nucleotide polymorphism (SNP) of WNT genes were selected from a genome-wide association study (GWAS). A total of 806 Chinese non-syndromic cleft lip patients, with or without cleft palate (NSCL/P) case-parent trios, were gathered from an international consortium. PoO effect of WNT pathway genes and its haplotypes were explored by log-linear models. Additional Wald tests were performed to assess: a) the heterogeneity of PoO effect between different maternal exposures, b) the interaction between PoO effect, c) maternal exposure to environmental tobacco smoke (ETS), and d) multivitamin supplementation during pregnancy. The threshold for statistical significance was adjusted as 3.47×10-4, according to Bonferroni correction.@*Results@#After quality control, a total of 144 SNPs within seven genes were included for analyses, among which 8 SNPs were of potential PoO effect (P<0.05). However, none of them achieved the statistical significance after Bonferroni correction. The haplotype rs4074668-rs12725747 (T-A) on WNT9A showed significant PoO effect, based on the haplotype test for PoO (P=2.74×10-4). In addition, no statistically significant interaction was found in further exploration of this haplotype under environmental exposures as ETS or multivitamin supplementation.@*Conclusions@#Genes in the WNT pathway may influence the NSCL/P risks through the potential PoO effect. Particularly, the haplotype rs4074668-rs12725747 (T-A) on WNT9A presented significant PoO effect on NSCL/P, statistically. From this current study, findings on WNT pathway related risks among the NSCL/P, need to be further validated by independent samples in the future.
ABSTRACT
Non-syndromic oral clefts (NSOC) are among the most common birth defects.The prevalence of NSOC is 1.13-1.30 per 1 000 live births in China,which is higher than those in other major ethnic groups.The etiology of NSOC is complex and heterogeneous,which involves both genetic and environmental risk factors.Although genome-wide association studies have identified a number of risk loci,these loci can only account for a small proportion of the heritability of NSOC.The next-generation sequencing research provides new ideas for further exploring the genetic risk factors of NSOC.This paper summaries the progress in the next-generation sequencing research of NSOC.
ABSTRACT
Non-syndromic oral clefts (NSOC) are among the most common birth defects.The prevalence of NSOC is 1.13-1.30 per 1 000 live births in China,which is higher than those in other major ethnic groups.The etiology of NSOC is complex and heterogeneous,which involves both genetic and environmental risk factors.Although genome-wide association studies have identified a number of risk loci,these loci can only account for a small proportion of the heritability of NSOC.The next-generation sequencing research provides new ideas for further exploring the genetic risk factors of NSOC.This paper summaries the progress in the next-generation sequencing research of NSOC.