Studies on the heredity of the human blood groups II. The A-B-O groups

Abstract

Summary and conclusions: The results of studies on the heredity of the A-B-O groups in a new series of 426 families with 649 children are presented. No exceptions were encountered to the multiple allele theory of heredity of the A-B-O groups and subgroups of A. During the period 1929 to 1952, a total of 1590 families with 3398 children have been tested for the A-B-O groups and only two contradictions to the Bernstein theory of inheritance were encountered, both apparently due to illegitimacy. Statistical analysis reveals a satisfactory agreement between the observed frequencies of blood groups in the children and those predicted under the theory of multiple alleles. While the A-B-O groups are reliable for medicolegal application in cases of disputed parentage, the subgroups of A should not be applied in such cases. The reason for this is that it has been impossible up to now to prepare anti-A₁ reagents of satisfactory titer, avidity, and specificity, comparable to anti-A and anti-B reagents which are available. As a result, subgrouping tests, particularly of newborn babies, do not give entirely reliable results.