Association between the polymorphism of CA dinucleotide repeat in intron 1 of NFκB1 gene and risk of breast cancer

NFκB1 encodes for a DNA binding subunit of NF-κB complex. Overexpression of NFκB1 has been reported in a number of human cancers including breast cancer. To date there has been no study on the relation between microsatellites in the NFκB1 gene and risk of breast cancer in Isfahan population. This study was aimed to investigate the existence of NFκB1 CA repeat polymorphism and its association with breast cancer risk in Isfahan population. This case-control study was conducted on 115 women with breast cancer and 115 healthy women. After DNA extraction from peripheral blood samples, desired sequence was amplified by polymerase chain reaction. Finally, CA repeat polymorphism was determined by amplified elements electrophoresis on polyacrylamide gel and determination of sequencing. According to the results of present study, 9 different alleles of the CA repeat in the range of 14 to 23 were detected in intron 1 of NFκB1 gene. The most common allele in both controls (29%) and cases (27%) allocated to (CA)16 allele. Due to the short allele (CA)14 frequency in patients (3%) and controls (0%), women who carry (CA)14 allele of NFκB1 gene were at significantly higher risk of developing breast cancer. Since the (CA)14 allele was observed only in patient women with the OR>8, it may be used as a prognosis marker for breast cancer development.