Detection of Somatic Mutation in Exon 12 of DNA Polymerase β in Ovarian Cancer Tissue Samples

Background: DNA polymerase &beta; (pol &beta;) is a key enzyme of base excision repair pathway. It is a 1-kb gene consisting of 14 exons. Its catalytic part lies between exon 8 and exon 14. Exon 12 has a role in deoxyribonucleotide triphosphate selection for nucleotide transferase activity. Methods: Genomic DNA was isolated from ovarian carcinoma samples. Single strand conformation polymorphism method was used to detect mutation in genomic DNA. Results: Twenty-four patients of the 152 pair of tumor samples (15.8%) exhibited a point mutation (C&rarr;G) in position 725 in exon 12, which shifts proline to arginine (P242R). Statistical analysis showed a significant (p < 0.001) relationship between pol &beta; mutation and the age of detection. Conclusion: This is a newly reported somatic mutation of pol &beta; in ovarian carcinoma patients from India.