Normal mammalian muscle differentiation and gene control of isocitrate dehydrogenase synthesis

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Chronon and the problem of anticipation (On two family cases of diabetes)

The Authors analyze the phenomenon whereby, in progressing from generation to generation, a hereditary disease may appear at an earlier, equal or later age (anticipation, repetition or posticipation, respectively). They believe that this represents the phenotypic effect of a temporal dimension of the gene, the “chronon”, which may reveal stability, plus-variance or minus-variance according to the standard genetic models. This interpretation provides an explanation of two family cases of diabetes mellitus, respectively exhibiting anticipation and posticipation, and repetition.

Agouti Locus: Homology of Its Method of Operation in Rats and Mice

The action of genes at the agouti locus in rats is similar to that of genes at the same locus in mice-the color phenotype of hairs is determined by the operation of agouti-locus alleles in the follicle, rather than in the melanocytes. Hairs produced by mouse skin growing on partially tolerant infant rat hosts show that rat melanocytes also respond to the agouti-locus genotype of mouse follicles. This constitutes the first example in vivo of the behavior of a cell of one species being completely determined by the genotype of an alien host species.

Serum Transferrin D Alleles in Australian Cattle

Transferrin phenotypes supporting the occurrence of two TiD alleles in cattle are illustrated. Segregation data and p:ene frequencies for five breeds for the two alleles TiD' and TiD' are presented.

Serum Albumin: Polymorphism in Man

Serums from 1015 individuals, mainly Norwegians, were studied by starch-gel electrophoresis. All but one showed the same albumin phenotype. The appearance of the exceptional sample on starch gel fits with that of a heterozygote. A genetic theory of two alleles Al(F) and Al(S) is proposed.