The HLA-G genotype is potentially associated with idiopathic recurrent spontaneous abortion.
The causes for recurrent spontaneous abortion (RSA) remain unknown in a large proportion of the cases. Human leukocyte antigen (HLA)-G and HLA-E are expressed on invasive trophoblast cells, and are supposed to confer to materno-fetal tolerance. A total of 14 different nucleotide sequences have been described for HLA-G, including one dysfunctional null allele (HLA-G*0105N), while five different sequences have been described for HLA-E. In this study, 78 RSA couples and 52 fertile controls were typed for HLA-G and HLA-E by direct sequencing or single strand conformational polymorphism (SSCP) respectively. The overall analysis showed no significant difference in allele frequencies for either HLA-G or HLA-E between the two groups. However, HLA-G allele frequencies in women who had suffered from five or more RSA differed significantly from fertile controls (P: = 0.001), and from women who had undergone three or four RSA (P: = 0.027). Detailed analysis demonstrated a significant increase in the proportion of the HLA-G alleles *01013 and *0105N in the whole group of RSA women compared with fertile controls (P: = 0.007). When studying the prognostic value of HLA genotyping for pregnancy outcome (n = 41), 31 patients (76%) gave birth to a living child without performing immunotherapy. Seven out of 10 (70%) couples suffering from a further RSA carried the HLA-G*01013 or *0105N allele, compared with 10 out 31 (32%) couples giving birth (P: = 0.06). This study suggests that the HLA-G genotype may be a contributing factor in RSA.
Pfeiffer
K A
KA
Department of Obstetrics and Gynecology, University of Bonn, Sigmund Freud Strasse 25, 53105 Bonn, Germany. k.pfeiffer@uni-bonn.de
Fimmers
R
R
Engels
G
G
van der Ven
H
H
van der Ven
K
K
D000026:Abortion, Habitual / Q000235:genetics* / Q000276:immunology; D000328:Adult; D005260:Female; D005838:Genotype; D006680:HLA Antigens / Q000145:classification / Q000235:genetics*; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000145:classification / Q000235:genetics*; D006650:Histocompatibility Testing; D006801:Humans; D011110:Polymorphism, Genetic; D018807:Polymorphism, Single-Stranded Conformational; D011247:Pregnancy; D011256:Pregnancy Outcome; D000097625:HLA-E Antigens
D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; D000097625:HLA-E Antigens