Determination of allelic polymorphism of codon F31I of STK15 gene in invasive ductal breast carcinoma

The carcinogenesis role of allelic polymorphism of codon F31I [T/A] of the serine/threonine kinase-15 (STK15) gene in geographic-dependent invasive ductal carcinoma is still controversial and worth to be studied. This study aimed to identify allelic polymorphisms of F31I codon in women with breast cancer compared to healthy controls in Sabzevar city, north-east Iran. This descriptive analytical study was conducted on 200 women including 100 patients and 100 healthy controls. DNA samples were extracted using a standard kit and codon F31I was amplified by polymerase chain reaction (PCR). The polymorphisms of different genotypes were identified by restriction fragment length polymorphism (PCR-RFLP) analysis and electrophoresis. The frequency of heterozygote phenylalanine/isoleucine (Phe/Ile) was 70 (35%) in the cancerous cases and 82 (41%) in controls. The frequency of homozygote isoleucine/isoleucine (Ile/Ile) was 30 (15%) in the patients and 18 (9%) in controls. The results did not show homozygote phenylalanine/phenylalanine (Phe/Phe) in either patients or controls. Moreover, there was a significant higher homozygote Ile/Ile in the patients compared to controls (P<0.034). For the first time, the study reports that there is a significant higher rate for homozygote Ile/Ile in cancerous patients compared to controls in Sabzevar city. Therefore, determination of allelic polymorphism of F31I codon of STK15 can be a clinically valuable test for diagnosis, prognosis and treatment purposes in breast cancer.