The C system of cattle blood groups. 2. Partial genetic map of the system.

20 cases of irregular inheritance of phenogroups in the C system of cattle blood groups were used to deduce a partial genetic map of this system, taking into consideration the 11 internationally recognized antigenic factors and the 4 additional factors recently described by Grosclaude et al. (1980). This partial map bears resemblance to that established by Bouw et al.

[The "hitch-hiking" effect of a selected gene and gamete combination (linkage disequilibrium): the example of 2 closely linked loci in the swine, Hal (halothane sensitivity) and PHI (phosphohexose isomerase)].

The observation of two lines of pigs selected differently for four generations confirms a recent theoretical work (Thomson, 1977) showing that a possible source of linkage disequilibrium may be the hitch-hiking effect of a selected locus (Hal) on another closely linked neutral locus (PHI).

The genetic map of the B system of cattle blood groups as observed in French breeds.

40 cases of irregular inheritance of phenogroups in the B system of cattle blood groups, that were presumed to have arisen from single crossing-over, have been used to establish a partial genetic map of this system. In addition, the relative positions in the map of several antigenic factors were inferred from relationships observed between particular phenogroups occurring in French breeds. The tentative map thus obtained shows an overall similarity to that established by Ruiterkamp et al.

[Preparation and partial physico-chemical characterization of sheep-serum transferrin].

Sheep-serum transferrin shows marked polymorphism and more than 20 alleles have been identified although only 4 or 5 of these have a frequency higher than 1%. Each of the alleles has two bands in starch-gel electrophoresis, corresponding to a major and a minor fraciton. This paper describes the isolation and partial characterisation of the two fractions from the transferrin of sheep homozygous for Tf B.