A new look at HLA genetics with particular reference to type-1 diabetes.

HLA genotypes were ascertained in 150 families with a diabetic child from the same geographical area. There was preferential zygotic assortment of the paternal HLA A1-B8 haplotype (63--65% compared with the expected 50%) in 69 diabetic families and 33 control families (pooled from elsewhere) who were informative for this haplotype. In diabetic families, the offspring also had an increased incidence of the maternal HLA A2-B15-Cw3 haplotype. Irrespective of which parent contributed the HLA A1-B8 haplotype, there was a significantly increased incidence of male children (63%) who inherited this particular haplotype. This probably explains the known excess of male diabetic children.