Summary and Conclusions
The bloods of 1334 mothers and their 1462 children were typed. Although 485 group O mothers with 516 children and 94 group AB mothers with 142 children were examined, not once did the combinations AB mother—O child or O mother—AB child appear. The authors' data together with Schiff's and Thomsen's, therefore completely support the Bernstein theory.
A survey of the literature shows that many apparent exceptions were found. On careful analysis of these cases, not a single completely proven exception to Bernstein's theory could be found.
It may therefore be concluded that although the existence of bona fide exceptions to the Bernstein theory cannot be entirely disproved, it is certainly true that of all the theories of heredity of blood groups, Bernstein's theory agrees best with the facts. Any true exceptions to this theory may be due to other factors complicating the mechanism of heredity.