The zebra shark Stegostoma tigrinum , a popular aquarium fish, is an endangered species that known to readily reproduce both sexually and through facultative parthenogenesis while in human care. Artificial insemination trials took place between 2011 2013 resulted the hatching of 2 produced (herein heterozygotes) 10 parthenogenetic sharks allowed for retrospective comparison growth, feeding long...

The sex-linked gene for tabby (Ta) in the mouse, in addition to its effects on fur and skin, has a characteristic dental syndrome (Griineberg, 1965). Some tabby heterozygotes have a spectacular mixture of molar teeth, some of which are normal, others which are tabby, and some which combine features of both. This prima facie evidence in favour of the single-active X-chromosome hypothesis of Lyon...

huntingtons disease is caused by a dominantly transmitted cag repeat expansion mutation that is believed to confer a toxic gain of function on the mutant protein. huntingtons disease patients with two mutant alleles are very rare. in other poly (cag) diseases such as the dominant ataxias, inheritance of two mutant alleles causes a phenotype more severe than in heterozygotes. in our evaluation, ...