Association of single nucleotide polymorphisms in the IRF6 gene with nonsyndromic cleft lip with or without cleft palate in Kinh Vietnamese patients.

BACKGROUND: The interferon regulatory factor 6 (IRF6) gene, which causes Van der Woude syndrome, is associated with nonsyndromic cleft lip with or without cleft palate (NSCL/P). Single nucleotide polymorphisms (SNPs) in the IRF6 gene were identified as susceptibility indicators of this defect in several populations. To further evaluate its role in this birth defect, we conducted this study with the aim of identifying allele frequencies, genotype frequencies, and associations of 5 SNPs (rs2235373, rs2235371, rs2235375, rs2013162, and rs2236907) in the IRF6 gene with NSCL/P in Kinh Vietnamese patients. METHODS: A total of 132 patients with NSCL/P and 132 healthy individuals were included in our study group. Direct sequencing was performed to genotype the tag SNPs. Genetic models were used to compare genotype and allele frequencies between the case and control groups. RESULTS: In the recessive model, the genotypes C/C of rs2236907, C/C of rs2013162, G/G of rs2235375, and A/A of rs2235373 were associated with an increased risk of NSCL/P, whereas there was no clear association between rs2235371 and the malformation in any genetic model. When subgroup analysis was performed, we observed a similar risk trend in the cleft lip and palate, cleft palate only and cleft lip only phenotypes. In haplotype analysis, haplotype models of 5 tag SNPs were associated with increased risks of this defect in all phenotypic models (ORGCGCC/CCAA = 23.64, 95% CI 12.28-45.49, p < 0.0001). CONCLUSIONS: These findings point to a considerable contribution of rs2236907, rs2013162, rs2235373, and rs2235375 to the NSCL/P defect in Kinh Vietnamese individuals.

Association of Single-Nucleotide Polymorphisms of MAFB Gene with Nonsyndromic Cleft Lip with or without Cleft Palate in Kinh Vietnamese Patients.

Background Cleft lip with or without palate (CL/P) is the most common orofacial birth defect. Single-nucleotide polymorphisms (SNPs) in MAFB gene (V-Maf avian musculoaponeurotic fibrosarcoma oncogene homolog B) were identified as susceptible to this defect in a genome-wide association study. To further evaluate its role in this birth defect, we conducted this study with the aim of identifying allele frequencies, genotype frequencies, and association of SNPs rs13041247, rs6065259, and rs6072081 of MAFB gene with nonsyndromic cleft lip/palate (NCL/P) in Kinh Vietnamese patients. Methods We performed case-control study involved 79 patients with NCL/P and 77 healthy controls. DNAs were extracted from participants' saliva and tetra-amplification refractory mutation system polymerase chain reaction (tetra-ARMS PCR) was used for genotyping SNPs. Results SNPs of MAFB gene were genotyped using the Tetra-ARMS PCR method. We found that genotype CT of rs13041247 was associated with an increased risk of NCL/P in Kinh Vietnamese (odds ratio TCTT [OR TC/TT ] = 1.63, 95% confidence interval [CI] = 0.83-3.19, p = 0.17). The G allele genotypes of SNP rs6072081 increase high risk for the malformation, statistically significant result (OR GG/AA = 7.06, 95% CI = 2.13-23.42, p < 0.001). There is no clear association between rs6065259 and CL/P (OR AA/GG = 0.75, 95% CI = 0.22-2.50, p = 0.32; OR AG/GG = 1.53, 95% CI = 0.79-2.97, p = 0.32). When the patients were divided into the phenotypic subgroups, there was a similar significant trend between the patients and controls for all SNPs. Conclusions Our study provides further evidence of role of MAFB gene variations with NCL/P defect in Kinh Vietnamese.