Association between novel HLA-G genotypes and risk of recurrent miscarriages: a case-control study in a South Indian population

Reprod Sci. 2008 Oct;15(8):817-24. doi: 10.1177/1933719107314061. Epub 2008 May 14.

Abstract

HLA-G is a nonclassical histocompatibility complex member associated with fetal tolerance of the mother observed during pregnancy. Despite its being a less polymorphic gene, a number of studies have evaluated the role of HLA-G gene polymorphisms on the risk of pregnancy-related complications. A 14-bp deletion polymorphism in exon 8 (3'UTR) was known to influence the levels of soluble HLA-G, differential splicing of the transcript, and also the induction of interleukin-10 secretion. The present study is aimed at evaluating the variations in exon 2 and exon 8 of the HLA-G gene for the risk of recurrent miscarriages in South Indian women. A total of 169 cases and 92 controls are included in the study. Six novel polymorphisms were identified, 2 of which are in intron 2 near the exon-intron junction and 4 of which are present downstream to the 14-bp deletion in 3'UTR. The exon 2 and intron polymorphisms failed to show any association. The T1570C and C1594A polymorphisms showed a significant association (P = .002 and .021) with the risk of miscarriage after categorization based on the 14-bp deletion. Linkage disequilibrium analysis showed that the T allele of T1570C is in linkage disequilibrium with the 14-bp deletion in cases but not in controls. In silico RNA folding studies indicate that the T allele forms a more stable secondary structure than the C allele, giving rise to a more stable transcript.The authors demonstrate a significant relation between the two 3'UTR polymorphisms and recurrent miscarriages.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abortion, Habitual / genetics*
  • Abortion, Habitual / immunology*
  • Case-Control Studies
  • DNA / chemistry
  • DNA / genetics
  • Female
  • Genetic Variation
  • Genotype
  • HLA Antigens / genetics*
  • HLA-G Antigens
  • Histocompatibility Antigens Class I / genetics*
  • Humans
  • India
  • Polymerase Chain Reaction
  • Polymorphism, Single Nucleotide
  • Pregnancy

Substances

  • HLA Antigens
  • HLA-G Antigens
  • Histocompatibility Antigens Class I
  • DNA