Hybrid dysgenesis is a condition found in certain interstrain hybrids of Drosophila melanogaster caused by the interaction of chromosomal and cytoplasmic factors. Germ-line abnormalities, including sterility, high mutability and male recombination, appear in the affected individuals. There are at lest two distinct systems of hybrid dysgenesis. We examined a Wisconsin wild population in two cons...

random monoallelic expression. Thus, the hypothesis of non-Mendelian inheritance remains valid, and the search for other mechanisms ensues. They do not exclude a complex situation in which both Mendelian and non-Mendelian mechanisms are at play. In the clinical part of this special issue, thyroid disorders associated with well-known genetic syndromes are carefully analyzed and reviewed. First, ...