The novel allele (3R) of the VNTR polymorphism in the XRCC5 promoter region dramatically decreases the gene expression

Polymorphism of variable number of tandem repeats (VNTR) in the promoter region of X-ray repair cross-complementing 5 (MIM: 194364, XRCC5 ; rs6147172) was reported. The aim of the present study is to evaluate the influence of this polymorphism on XRCC5 mRNA levels. Genotypes of XRCC5 VNTR were determined by high resolution of melting analysis (HRMA). The quantitative XRCC5 mRNA expression (compared to s-actin expression) among 0R/1R, 1R/2R, and 1R/3R genotypes was investigated. There was a negative correlation between the overall number of tandem repeats and XRCC5 expression ( r = −0.965, df = 7, P XRCC5 decreased as function of number of tandem repeats. The 3R allele of the VNTR polymorphism in the XRCC5 promoter region dramatically decreases the gene expression.