title: XPD Lys751Gln increases the risk of breast cancer.
abstract: Breast cancer incidence has been on the increase in south Indian women. Polymorphisms in DNA repair genes modify an individual's risk to cancer. XPD (Xeroderma pigmentosum D), a DNA helicase gene involved in nucleotide excision repair and transcription coupled repair, may affect an individual's DNA repair capacity, particularly that of bulky adducts. This case-control study (250 breast cancer cases and 500 healthy controls) aimed to investigate the role of the XPD Lys751Gln polymorphism as a risk factor in the development of breast cancer. Genotyping was performed using the Taq Man allelic discrimination assay. Immunohisto-chemistry was used to quantitate the level of polycyclic aromatic hydrocarbon (PAH) adducts in biopsy samples obtained from the breast cancer patients. Results showed that the XPD Gln/Gln genotype was significantly associated with an increased risk of breast cancer (OR, 1.75; 95% CI 1.02-2.80), particularly in premenopausal female patients (OR, 2.6; 95% CI 1.33-4.79). PAH adduct levels were significantly higher in the cases with breast cancer as compared to the normal breast tissue. This study reveals that XPD may play a role in increasing breast cancer risk particularly in premenopausal females.
authors.affiliation: Department of Molecular Oncology, Cancer Institute (WIA), Adyar, Chennai 600020, India.
authors.forename: Mani
authors.initials: M
authors.lastname: Samson
authors.forename: Shirley Sunder
authors.initials: SS
authors.lastname: Singh
authors.forename: Ranganathan
authors.initials: R
authors.lastname: Rama
authors.forename: Veluswami
authors.initials: V
authors.lastname: Sridevi
authors.forename: Thangarajan
authors.initials: T
authors.lastname: Rajkumar