Polymorphisms in oestrogen and progesterone receptor genes: possible influence on prolactin levels in women

OBJECTIVE: Oestrogen and progesterone are known to influence the release of human prolactin. The present study was undertaken in order to investigate the possible influence of polymorphisms of the genes encoding the oestrogen receptor (ER)alpha, ERbeta and the progesterone receptor (PGR), on prolactin levels in premenopausal women. DESIGN AND MEASUREMENTS: Serum levels of prolactin were measured in the follicular phase of the menstrual cycle. Subjects were genotyped with respect to a TA repeat polymorphism of the ERalpha gene, a CA repeat polymorphism of the ERbeta gene, and two polymorphisms of the PGR gene: one insertion polymorphism (PROGINS) and one single nucleotide polymorphism (G331A). SUBJECTS: A population-based cohort of 270 42-year-old women. RESULTS: The CA repeat polymorphism of the ERbeta gene and the G331A polymorphism of the PGR gene appeared to be associated with prolactin levels. In contrast, we found no evidence for an influence of the PROGINS polymorphism of the PGR gene or the TA repeat polymorphism of the ERalpha gene on the levels of this hormone. CONCLUSIONS: These data suggest that genetic variants of both the ERbeta and the PGR may influence prolactin release.