title: Role of 14-bp deletion/insertion polymorphism in exon 8 of the HLA-G gene in recurrent spontaneous abortion patients.
abstract: BACKGROUND
  Human leukocyte antigen (HLA)-G belongs to the nonclassical Class I major histocompatibility complex, and is predominantly and specifically found on the extravillous cytotrophoblast cells of the placenta. HLA-G has been postulated as an important immunotolerant molecule in maintaining successful pregnancy and maternal tolerance of the semiallogenic fetus. Recent reports indicate that the 14-bp deletion/insertion polymorphism in exon 8 of the 3'UTR region of the HLA-G gene influences the HLA-G mRNA stability and isoform splicing patterns, thus modulating the levels of HLA-G expression.
  
  
  OBJECTIVE
  The aim was to study the 14-bp deletion/insertion polymorphism in exon 8 of the 3'UTR region of the HLA-G gene.
  
  
  METHODS
  A total of 50 women with unexplained three or more recurrent spontaneous abortions (RSAs) and 41 normal healthy control women who have had normal pregnancies and were genotyped for the 14-bp deletion/insertion polymorphism were genotyped for the 14-bp deletion/insertion polymorphism by polymerase chain reaction for exon 8-specific primers
  
  
  RESULTS
  It was found that the 14-bp allele deletion frequency was lower in patients (67%) versus controls (73%), while 14-bp allele insertion was higher among patients (33%) versus controls (9%). Similarly, the homozygous deletion halotype was higher among the controls (80.48%); the heterozygous insertion deletion haplotype (34%) and homozygous insertion haplotype (16%) were higher in RSA patients. The HLA haplotype HLA A*02:11_B*40:06:01:01 was increased among RSA women compared to controls.
  
  
  CONCLUSIONS
  Our results suggest that 14-bp deletion/insertion polymorphisms might have importance in the outcome of pregnancy and the 14-bp deletion polymorphism in exon 8 of the HLA-G gene may be important from an evolutionary perspective of successful pregnancy.
authors.affiliation: Department of HLA and Transplantation, National Institute of Immunohaematology, KEM Hospital Campus, Parel, Mumbai, India.
authors.forename: U
authors.initials: U
authors.lastname: Shankarkumar
authors.forename: A
authors.initials: A
authors.lastname: Shankarkumar
authors.forename: Z
authors.initials: Z
authors.lastname: Chedda
authors.forename: K
authors.initials: K
authors.lastname: Ghosh