120: Progesterone receptor gene polymorphisms and pregnancy-related parameters in a racially diverse population

Abstract

PARAMETERS IN A RACIALLY DIVERSE POPULATION DANIEL SKUPSKI, IARA LINHARES, NEIL NORMAND, DEVRIM SEZEN, OKSANA BABULA, SHARI GELBER, ANN MARIE BONGIOVANNI, STEVEN S. WITKIN, Cornell University, Flushing, New York, Weill Medical College of Cornell University, Obstetrics and Gynecology, New York, New York, Cornell University Medical College, Obstetrics and Gynecology, New York, New York, Weill Medical College of Cornell University, Obstetrics and Gynecology, New York OBJECTIVE: The progesterone receptor (PR) exists in two isoforms, PR-A and PR-B. Both are products of the same gene and have different promoter sites. Progesterone binding to PR-B activates progesterone-responsive genes while binding to PR-A is without agonist activity and inhibits progesterone functions. A single G A polymorphism at position 331 in the PR gene results in increased production of PR-B, a decrease in the PR-A/PR-B ratio and has been associated with abnormal endometrial development. Since progesterone has diverse functions during gestation, we hypothesized that possession of the G A polymorphism would influence pregnancy-related parameters. STUDY DESIGN: The borough of Queens has the most diverse racial/ethnic population in the United States. Buccal swabs were collected from 469 motherinfants pairs (2:1, term birth to preterm birth) and tested for the PR G A polymorphism by gene amplification. Clinical and demographic parameters were collected and analyzed after completion of all laboratory testing. RESULTS: Maternal carriage of the variant A allele was identified in 5/53 (9.4%) White women, 9/111 (8.1%) Hispanics, 1/69 (1.4%) Blacks, 2/168 (1.2%) Asians and 0/58 East Indians (O2 for trend .0001). Only in Hispanic women was maternal allele A carriage associated with a higher median pre-pregnancy weight (75.2 kg vs. 63.0 kg, P .048), as well as an elevated weight at delivery (95.9 kg vs. 79.7 kg, P .002). Evaluating the population as a whole, maternal A allele carriage occurred almost equally in women with a term (10/286, 3.5%) or preterm (8/183, 4.4%) birth. However, among women who delivered preterm, the A allele was associated with a prior history of spontaneous preterm birth [(4/21 preterm, (19.0%) vs. 4/156 at term, (2.5%) (P .007)]. CONCLUSION: The G A PR polymorphism varies in frequency among different ethnic groups. Allele A carriage may influence maternal weight gain in Hispanic women and susceptibility to a repeat spontaneous preterm birth. Analysis of Hispanic women for this polymorphism may have clinical utility.