HLA antigen sharing in Italian couples in which women were affected by gestational trophoblastic tumors.

Problem: The development of gestational trophoblastic tumors (GTT), in which genetic factors are strongly involved, is a rare event. To test the possibility that gene(s) linked to the Major histocompatibility Complex (MHC) may have a role in both embryo growth and tumor development, the HLA typing was performed on patients affected by GTT and on their partners.
Method: The study group of sixteen couples, in which the women were affected by an invasive mole or choriocarcinoma, and the control group of thirty normal fertile couples without history of spontaneous abortion or GTT were typed for class I and class II HLA antigen.
Results: The results showed no differences in single HLA-A and B antigen frequency between GTT couples and controls. In HLA-DR, locus an increased frequency of DR-6 antigen was observed (p < 0.05). No differences were observed in the frequency of number of antigens shared. When considering the single locus no differences were found in the sharing of the antigens of the A and B locus, while the frequency of antigenic sharing for DR locus was significantly higher in GTT couples with respect to controls (p < 0.025). Furthermore a higher frequency of Bw35-DR5 antigenic combination was found in GTT partners than in controls (P < 0.02).
Conclusions: These data represent a confirmation of the existence of a MHC linked gene(s) influencing the GTT development.