Published online by Cambridge University Press: 01 August 2014
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.