Prolactin receptor gene polymorphisms are associated with gestational diabetes

Human placental lactogen (hPL) acts via the prolactin receptor (PRLR) on maternal β-cells to mediate increases in β-cell mass and function during normal pregnancy. This interaction between hPL and PRLR is essential to maintain normal glucose homeostasis and to address the increased metabolic demands of pregnancy. Given the importance of the PRLR-hPL axis in pancreatic islet cell adaptation to pregnancy, we hypothesized that genetic variation in the PRLR gene could influence risk of development of gestational diabetes mellitus (GDM). DNA samples from 96 mothers affected by GDM and 96 unaffected cases were genotyped for 8 selected single nucleotide polymorphisms (SNPs) in PRLR. Significant associations were identified in two SNPs analyzed. The minor alleles of PRLR SNPs rs10068521 and rs9292578 were more frequently observed in GDM cases than controls and were associated with a 2.36-fold increased risk for GDM in those carrying the minor allele. SNPs of the PRLR gene 5' UTR and promoter region are associated with increased risk for GDM in a population of Chilean subjects.