Recurrent spontaneous abortions patients have more −14 bp/+14 bp heterozygotes in the 3′UT region of the HLA‐G gene in a Chinese Han population

Abstract

Although human leukocyte antigen (HLA)-G gene polymorphism is low, it may influence levels of protein expression and, in some cases, has been associated with pregnancy diseases. Apart from the 23 HLA-G alleles, including a null allele known as HLA-G*0105N, a 14-bp deletion or insertion in the 3'UT region also contributes to the HLA-G gene polymorphism. In order to discover any correlation between the 14-bp deletion polymorphism and pregnancy diseases, we isolated the genomic DNA from 24 recurrent spontaneous abortions (RSA) patients and 88 normal fertile control individuals using the salted out method. Exon-8 of HLA-G gene of the two groups was amplified by polymerase chain reaction, respectively, and analyzed by electrophoresis on 9% nondenaturing polyacrylamide gel and stained with ethidium bromide. Differences between the two groups were compared using the chi(2) test. The results were there was no significant difference in allelic frequencies of 14-bp deletion polymorphism between normal control and RSA patients; frequency of -14 bp/+14 bp heterozygotes was significantly increased in RSA patients as compared with normal fertile controls. Our results are similar to a study of Indian women but contradictory to a study of Danish women. This discrepancy may be due to ethnic differences.

DISTRIBUTION PATTERNS OF ALLELES AND GENOTYPES FOR HLA-G 3'UTR 14-bp ins/del IN MOTHERS OF CHILDREN WITH CONGENITAL HEART DEFECTS OR REPRODUCTIVE LOSSES AT EARLY GESTATION TERMS

“…Проведенный анализ литературных данных показал, что аллель HLA-G 3'UTR 14-bp ins и со-ответствующий гомозиготный генотип достовер-но чаще встречается у женщин с ранними репро-дуктивными потерями [5,22,25]. Известно, что для HLA-генов всегда имеет место кодоминант-ная модель наследования, то есть постоянное участие в иммунных процессах всех унаследован-ных аллелей [15].…”

Genetic regulation of recurrent spontaneous abortion in humans

“…[81] Two other negative studies were published -one in 2010 that analyzed 143 RSA and 150 control couples in the Indian population [82] and another one in 2012 on an Iraqi population of 50 RSA and 50 control women. [83] By contrast, Xue et al discovered an excess of heterozygotes in Chinese RSA women, [84] while another more recent study from China indicated an increased number of +14 bp homozygotes in the RSA women. [85] Near the 14-bp Ins/Del, two polymorphisms (T1570VC and C1594A) were detected and found to be associated with RSA risk; [86] T1570C was in LD with the cases but not with the controls.…”

Relationship between HLA-G polymorphism and susceptibility to recurrent miscarriage: A meta-analysis of non-family-based studies

“…Among these, 4 studies were excluded due to duplicate publications [32][33][34][35], three had incomplete data on allele and genotype frequency which we failed to get by emails to the corresponding authors [36][37][38], and an additional one was excluded due to the absence of a control group [39]. Consequently, the remaining 17 case-control studies which examined the association between the HLA-G 14-bp polymorphism and RM were finally included [12,17,[25][26][27][40][41][42][43][44][45][46][47][48][49][50][51] (Fig. 1).…”

“…Association between RM and HLA-G 14-bp insertion/deletion polymorphism allele Sixteen studies were included in assessing the association between HLA-G 14-bp insertion/deletion polymorphism allele and RM [12,17,[25][26][27][40][41][42][43][44][45][46][47][48][49][50]. As shown in Fig.…”