Association of CYP1A1 M2 (A2455G) Polymorphism with Susceptibility to Breast Cancer in Mazandaran Province, Northern Iran: A Case–control Study

Ghazaleh Khalili Tanha, Ali Barzegar, Novin Nikbakhsh, Zarbakht Ansari-Pirsaraei


Background: Breast cancer is one of the most frequent women malignancies in the world. The cytochrome P450 1A1 (CYP1A1) is a key enzyme in xenobiotics metabolism. Moreover, CYP1A1 plays a critical role in the etiology of breast cancer by involving in 2‑hydroxylation of estrogen. Therefore, single‑nucleotide polymorphisms (SNPs) of its coding gene have been verifed to be important in cancer susceptibility. The aim of the study was to evaluate the association of CYP1A1 M2 (A2455G) includes rs1048943 of this SNP polymorphism with the risk of breast cancer in Mazandaran province.

Methods: Ninety‑six breast cancer patients with known clinicopathological
characters and 110 healthy women as control were genotyped for CYP1A1 M2 polymorphisms by the restriction fragment length polymorphism technique.

Results: The analysis of CYP1A1 gene (polymorphism M2) showed that the frequency of homozygous wild genotypes (AA), heterozygous (AG), and mutant genotype (GG) in the patient group, respectively, 78%, 22%, and 0%, and also the frequency of genotypes AA, AG, and GG in healthy included 82%, 16%, and 2%, respectively. Statistical analysis by Logistic regression model at P < 0.05 showed no
signifcant correlation between polymorphisms in CYP1A1M2 and breast cancer risk (odds ratio = 0.84, confdence interval = 0.33–2.17).

Conclusions: The results indicated that the M2 allelic genotypes were signifcantly associated neither with breast cancer risk nor with clinicopathological characteristics in Mazandaran province.

Keywords: Breast neoplasms, cytochrome P‑450, Iran, polymorphism, restriction fragment length

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