New research has identified a gene involved in serotonin (5-hydroxytryptamine [5-HT]) control that can delay ejaculation, and determines whether a man is likely to experience premature ejaculation ...

Precisely how lowered levels of the gene product, an enzyme called hexoseaminidase A, protect against TB isn't known. Balanced polymorphism may explain why cystic fibrosis is so common- the ...

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