Dr David Drucker at Manchester University has identified a "cot death gene".

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At first, of course, the rediscovery of the Mendelian gene was thought to be the death knell for Darwinism.

FORBES: Evolution and Embodied Physiology

The gene is thought to cause the death of cells, which can in turn lead to diseases including cancer.

BBC: Chicken virus study sheds light on human cancers

High activity levels of a third gene, CHI3L1 were common in cancers showing a larger degree of cell death.

BBC: Childhood cancer genes pinpointed

Sometimes these viruses have provoked strong immune reactions which is what caused the death of Jesse Gelsinger, an 18-year-old American who had a damaged gene that prevented his liver from making an enzyme to break down ammonia.

ECONOMIST: The prospects for using genes as a therapy may be improving