Purpose: Germline variants of the CHEK2 gene have been shown to act as low-penetrance cancer susceptibility alleles for a wide range of human malignancies. CHEK2 I157T has particularly been linked to colorectal cancer (CRC) risk. We aimed at establishing the population frequency and contribution of this variant to colorectal carcinogenesis in Bulgaria.
Methods: We have genotyped 802 population controls and 343 CRC patients from Bulgaria for the CHEK2 I157T variant.
Results: Heterozygous were 9 of 343 patients (2.62%, odds ratio/OR=1.0, 95% confidence interval/CI = 0.42 - 2.33, p=0.99% and 21 of 802 controls (2.62%). Higher frequencies were found among patients with multiple polyposis (2/40, 5%, p=0.28) and the rarer mucinous histology (1/11, 9.09%, p= 0.26).
Conclusion: We conclude that CHEK2 I157T is not relevant for CRC risk in Bulgaria, but studies on a larger scale might help evaluate its possible significance in respect to disease characteristics.