A polymorphism in the CYP17 gene and intrauterine fetal growth restriction

Intrauterine fetal growth restriction is a multifactorial disorder, and its aetiology includes both environmental and genetic components. We aimed to investigate whether maternal genetic polymorphisms of metabolic enzymes affects fetal growth and pregnancy duration. Genomic DNA was obtained from 134 women who experienced singleton deliveries beyond 24 weeks of gestation. Maternal age, birth weight, gestational age at birth and frequencies of fetal growth restriction, prematurity and pregnancy-induced hypertension were compared among genotypic subgroups of cytochrome p450 (CYP) and glutathione S-transferase (GST) genes. The polymorphisms of CYP1A1 (MspI), CYP17 (MspAI) and GSTP1 (BsmAI) genotypes, and the presence or absence of GSTM1 and GSTT1 genes were analysed by PCR-based methods. The frequency of fetal growth restriction (<10th percentile/<-1.5 SD; 22.7%/11.4%) in 44 women who were homozygous for the A1 allele (A1A1) of CYP17 was significantly higher than that (7.8%/2.2%) in 90 women who carried the A2 allele (A1A2/A2A2) of CYP17 (P < 0.05), with an odds ratio =3.41 (95% confidence interval = 1.18-9.84). The gestational age at birth (mean +/- SD, 37.5 +/- 3.1 weeks) in 67 women with GSTM1 null genotype was significantly lower than that (38.5 +/- 2.4 weeks) in 67 women who carried GSTM1 (P < 0.05). The polymorphism of CYP17 that encodes the cytochrome p450c17alpha enzyme might be associated with the pathophysiology underlying fetal growth restriction.