Vitamin D receptor polymorphisms and growth until adulthood after very premature birth

Abstract

The accretion of bone mass is often impaired in preterm infants, which may contribute to postnatal growth failure. We tested the effects of the vitamin D receptor single-nucleotide polymorphisms (SNPs) c1521g, Fok1, Bsm1, and Taq1 on linear growth up until adulthood in 341 subjects born very prematurely (i.e., <32 weeks of gestation) from the Dutch Project On Preterm and Small-for-gestational-age infants cohort. The GG genotype of the c1521g SNP was associated with a 0.36 [95 % confidence interval (CI), 0.02–0.69] SD taller adult stature and the ff genotype of the Fok1 SNP with a 0.38 SD (95 % CI, 0.02–0.75) taller adult stature. Interaction between these genotypes on stature was observed from the age of 1 year onward (albeit nonsignificantly before the age of 5 years), with adult height being 1.54 (95 % CI, 0.44–2.63) SD taller in subjects carrying both genotypes. The Bsm1 and Taq1 variants were both associated with faster catch-up growth until 2 years of age. Statistical correction for potential confounders did not change our results. We conclude that homozygosity for the minor alleles of both c1521g and Fok1 is associated with a taller adult stature in subjects born very prematurely. The minor alleles of Bsm1 and Taq1 are associated with faster catch-up growth in infancy.