Androgen receptor exon 1 CAG repeat length and risk of ovarian cancer

Epidemiological studies indicate that ovarian cancer is an endocrine-relate d tumour. We conducted a case-control comparison to assess the androgen rec eptor (AR) exon I polymorphic CAG repeat length (CAG(n)) as a risk factor f or epithelial ovarian cancer, AR CAG(n) was determined for 319 case subject s with ovarian adenocarcinoma and 853 unaffected control subjects (comprisi ng 300 unrelated adult female monozygotic twins, and 553 adult females samp led randomly from the population using the electoral rolls), The CAG(n) dis tributions of case subjects and control subjects were compared as a continu um, and by dichotomising alleles according to different CAG(n) cut-points. Logistic regression was used to calculate age-adjusted odds ratio (OR) esti mates, Analyzed as a continuous variable, there was no difference between c ase subjects and control subjects for the smaller, larger or average allele sizes of the CAG(n) genotype, before or after adjusting for age. The mean (95% CI) for the average GAG, was 22.0 (21.8-22.2) for case subjects and 22 .0 (21.9-22.1) for control subjects (p > .9). Analysis of CAG(n) as a dicho tomous variable showed no difference between case subjects and control subj ects for the median cutpoint (greater than or equal to 22), or for another cut-point previously reported to act as a modifier of breast cancer risk (g reater than or equal to 29), Our data provide no evidence for an associatio n between ovarian cancer risk and the genotype defined by the AR exon I CAG (n) polymorphism, although we cannot exclude smalt effects, or threshold ef fects in a small subgroup. (C) 2000 Wiley-Liss, Inc.