Immunogenetic study of couples with recurrent spontaneous abortions.
OBJECTIVE
Clinical observations suggest that genetic and immunologic disparity could be a factor in fecundity. The HLA system (HLA) is polymorphic and TLX (Trophoblast Lymphocyte Cross-Reactive), which is also polymorphic, seems to be linked to it. The immunologic hypothesis follows that excessive HLA and TLX-sharing could explain the rejection of a semi-allogenic blastocyst. Study objectives are therefore twofold; To determine whether or not there is significant HLA-sharing between spouses with unexplained recurrent spontaneous abortions (RSA) and to determine whether or not there is an association between some HLA specificities and RSA.


METHODS
The study includes only Caucasian couples that have had three successive spontaneous abortions. These were distributed in two groups: Group E: 18 couples either with known aetiology or with secondary RSA; Group U: seven couples with unexplained primary RSA; Control group C: 21 couples with at least two children and no spontaneous abortions. Tissue typing for HLA-A and B molecules was performed using serotyping methodology based on lymphocytotoxicity reaction. The different DRB1 alleles (class II) were determined by oligotyping with a non-radioactive reverse dot-blot methodology.


RESULTS
Statistical comparison shows that the number of couples without shared specificity is not significantly different between the three groups for each locus independently and for the set of three. Our results show also that the allelic frequencies are not significantly different between the three groups.


CONCLUSIONS
There is no higher HLA-sharing in couples with RSA than in fertile couples. Similarly, no particular HLA specificity can be associated with the RSA.
Bellingard
V
V
Department of Obstetrics and Gynecology, Montpellier University 1, Hospital Arnaud de Villeneuve, France.
Hedon
B
B
Eliaou
J F
JF
Seignalet
J
J
Clot
J
J
Viala
J L
JL
D000026:Abortion, Habitual / Q000235:genetics* / Q000276:immunology*; D000483:Alleles; D001483:Base Sequence; D005260:Female; D015234:HLA-A Antigens / Q000235:genetics; D015235:HLA-B Antigens / Q000235:genetics; D006684:HLA-DR Antigens / Q000235:genetics; D059811:HLA-DRB1 Chains; D006239:Haplotypes; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D011247:Pregnancy
D015234:HLA-A Antigens; D015235:HLA-B Antigens; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains