A Swiss family showing independent segregation of the Lutheran and Swann genes.

A family is reported in which the parents' mating is of the 'double back-cross' type with respect to the Sw, Lu and Se genes. The inheritance of these genes in the children shows, with reference to a possible linkage between Sw and the two other loci, four non-recombinants and three recombinants (or vice versa). The inheritance of the Lu and Se genes shows the well-known linkage between these two loci, with no instance of recombination. It is concluded that there is no evidence for close linkage between Sw and Lu-Se, and that the suggestion of a Sw-Lu linkage found in a family studied previously was due to chance.