Because of the complementary roles of the these two genes, a protective Factor B variation can protect against AMD, even if one carries a risk-increasing variant of Factor h, and vice versa.

因为这两个基因的附属作用，即使携带了因子h的一个危险性突变，因子b的一个保护性突变也可以对抗amd。反之亦然。

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Beyond obvious mood spoilers such as poor hygiene and bad breath, we each have a distinct natural scent that appears to guide us toward choosing a partner with compatible DNA. Scientists have found that women prefer the scents of men with a complementary set of genes that code for the immune system.

CNN: The science of kissing