Interaction of maternal peroxisome proliferator-activated receptor gamma2 Pro12Ala polymorphism with fetal sex affects maternal glycemic control during pregnancy

Abstract

It was suggested that fetal sex may substantially affect maternal glycemic control during pregnancy in genetically susceptible mothers. The peroxisome proliferator-activated receptor gamma2 (PPARgamma2) Pro12Ala polymorphism is known to affect glycemic control and may act in a sex-specific manner. This polymorphism is thus an attractive candidate to test this hypothesis using a second independent functionally relevant polymorphism. We analyzed the impact of fetal sex on maternal glycemic control during pregnancy in relation to the maternal PPARgamma2 Pro12Ala polymorphism. Two-thousand fourteen Caucasian women without preexisting diabetes and preexisting hypertension with singleton pregnancies delivering consecutively at the Charité obstetrics department were genotyped. Glycemic control was analyzed by measuring total glycated hemoglobin at birth. Correction for confounding factors and multiple testing was considered in the analysis. The maternal PPARgamma2 Pro12Ala polymorphism without consideration of fetal sex had no effect on blood pressure, new onset of proteinuria and total glycated hemoglobin at delivery. Mothers carrying both G alleles (GG genotype) delivering a girl had a higher (P = 0.015) total glycated hemoglobin (6.81 or - 0.50%) versus mothers carrying the same alleles but delivering boys (5.85 + or - 0.58%). Comparing mothers with the GG genotype delivering girls with mothers with CC or CG genotypes also delivering girls (6.32 + or - 0.72%) revealed a significantly higher maternal total glycated hemoglobin at delivery in the former group (P < 0.009). Fetal sex/sex chromosomes may substantially affect maternal glycemic control in mothers who are carriers of the GG alleles of the PPARgamma2 Pro12Ala polymorphism.