Objective: To evaluate the association between AXIN2, CDH1 and IRF6 with oral clefts in a cohort from Latvia.
Material and methods: 283 unrelated individuals, 93 born with isolated oral clefts and 190 individuals born without any structural abnormalities were evaluated. Cleft type and dental anomalies outside the cleft area were determined by clinical examination. Four SNPs were selected for this study: rs2240308 and rs11867417 in AXIN2; rs9929218 in CDH1; and rs642961 in IRF6. Genotypes were determined by polymerase chain reaction using the Taqman assay method from a genomic DNA sample extracted from whole blood. Allele and genotype frequencies were compared between individuals born with or without oral clefts using the PLINK program.
Results: Tooth agenesis was the most frequent dental anomaly found among individuals born with oral clefts (N=10; frequency 10.8%). The allele A in the IRF6 marker rs642961 was associated with all combined types of oral clefts (OR=1.74; CI 95% 1.07-2.82) and with cases with cleft lip with or without cleft palate (OR=1.88, CI 95% 1.15-3.01; p=0.007).
Conclusions: The IRF6 AP-2a binding site promoter polymorphism is associated with isolated oral clefts in Latvia.