Objective To understand the genetic polymorphism of the CYP 19 Δ3(TTTA)n Allele.
Methods Total DNA was extracted by Chelex-100 from blood samples of 155 unrelated Chinese women.Allele genotype frequencies for the CYP19Δ3(TTTA)n Allele were established from the total DNA using locus-specific prime PCR, Followed by electrophoresis of PCR products in denaturing polyacryamide gels and subsequent detection by silver staining.
Results Alleles with 11 repeats in Chinese women were more frequent than that in Japanese women.(TTTA)8 Alleles in Chinese women were more frequent than that in Japanese women and less frequent than that in Caucasian women.(TTTA)7 Alleles in Japanese women were more frequent than that in Chinese women; And(TTTA)7 Alleles in Chinese women were more frequent than that in Caucasian women.Δ3(TTT A)7 Alleles in Caucasian women were more frequent than that in Chinese and Japanese women.(TTTA)(n≥10)Alleles in Caucasian women were more frequent than that in Chinese and Japanese women.
Conclusion The frequencies distribution of the CYP 19Δ3(TTTA)n Allele are different among Chinese, Japanese and Caucasian women.There maybe no relationships between(TTTA)(n≥10)Alleles frequency and breast cancer risk.