Association between Transforming Growth Factor Alpha TaqI Polymorphism and Susceptibility to the Nonsyndromic Cleft Lip and/or Palate in an Iranian Population: A Case Control Study

Abstract

Background: The TGF-α TaqI C >T polymorphism is a well-characterized variant for nonsyndromic cleft lip and/or palate (NS CL/P), but it has shown inconsistent results of association with nonsyndromic CL/P across a number of studies. Thus, we have performed this case-control study to clarify the association between the TGF-α TaqI C >T polymorphism and NS CL/P risk. Methods: One-hundred ten cases with NSCL/P and 110 controls were recruited to the current study. We have genotyped the TGF-α TaqI C >T polymorphism using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The odds ratio (OR) and 95% confidence interval (CI) were applied for strength of association TGF-α TaqI C >T polymorphism with NSCL/P. Results: The TGF-α TaqI C >T polymorphism CC, CT and TT genotypes frequencies in the NSCL/P cases were 30.9%, 57.3% and 11.8%, respectively while the corresponding frequencies in the controls were 37.3%, 52.7% and 10.0%, respectively. The frequency of C and T alleles in the case were 59.5% and 40.5%, respectively while the corresponding allelic frequencies in the controls were 63.6% and 36.4%. There was no significant difference in the genotype and allele frequency for TGF-α TaqI C >T polymorphism between cases and controls. The minor allele frequency (MAF) of TGF-α TaqI C >T polymorphism among healthy controls was 0.36. Conclusion: Our study indicates that the TGF-α TaqI C>T polymorphism was not significantly associated with increased risk of NS CL/P in the Iranian population. However, our results still need to be confirmed by further large and well-designed case-control studies.