The effect of parental HLA compatibility on the expression of paternal haplotypes in offspring

The compatibility of HLA-A,-B expression between mother and offspring was examined in 410 families serologically tissue typed within a single transplant lab from 1972 thru 1982. The study group included 410 mothers of 1719 children (range 2–13/mother), with 352 one-father and 58 multiple-father families. There were seven cases of monozygous twins and seven cases each of maternal and paternal allelic recombination. The degree of haplotype matching between the oldest offspring and subsequent siblings was within the expected range of distribution. The number of maternal HLA-A,-B antigens matched or mismatched with paternal antigens of the offspring did not show a significant difference between early born or late born siblings either in one-father or multiple-father families. In addition, where the mother showed significant sensitization to paternal HLA-A,B antigens there was no apparent selection against the incompatible paternal HLA antigens or associated haplotypes in subsequent offspring. These data suggest that maternal HLA compatibility with the father is not a significant selective factor in determining the expression of paternal haplotypes in offspring.