电影中情侣由于基因结缘和分离的故事，在现实生活中似乎有些荒诞。但中国和法国等国研究人员最近发现，人体内的一个基因对部分人类种群的择偶可能会产生一定影响。
法国国家科研中心9月12日发表新闻公报说，这个名为“主要组织相容性复合体”（MHC）的基因，在人体免疫功能方面发挥着重要作用。它能使人体及时发现进入体内的致病因子，并启动免疫系统进行防御。
科学家此前曾通过动物实验发现，MHC基因还会影响一些动物对配偶的选择，如老鼠、鸟类在择偶时都会趋向于选择与自身MHC基因不同的异性，因为这样做可以提高后代的基因质量，增强对病原体等的抵抗力。
早先的研究发现，MHC基因多样性较高的动物个体，对外界病原体的抵抗力较强，而且这些动物通过嗅觉或叫声，就能分辨出MHC基因多样性的高低。但围绕这种基因是否对人类择偶也起到同样作用，科学界始终看法不一。
就此，法国国家科研中心、中国科学院上海生命科学研究院和英国牛津大学等机构的研究人员合作，对尼日利亚和美国两个不同种群人的基因组进行了研究。他们在尼日利亚的约鲁巴人和美国犹他州的欧洲裔美国白人中各选取了一些夫妇，分析他们MHC基因的异同。结果发现，由于约鲁巴人大多为包办婚姻，并非自行择偶，夫妇之间MHC基因的差异不是十分明显；而欧洲裔美国人择偶比较自由，夫妻之间MHC基因的差异就相对较大。
研究人员认为，这一结果表明MHC基因与部分人类种群的择偶之间存在一定关联，但他们还需要对更多人类种群进行研究，以更好地了解MHC基因的特点和它所发挥的作用。
上述研究结果发表在最新一期《公共科学图书馆·遗传学》（PLoS Genetics）杂志上。（生物谷Bioon.com）
生物谷推荐原始出处：
PLoS Genetics，doi:10.1371/journal.pgen.1000184，Rapha?lle Chaix，Peter Donnelly
Is Mate Choice in Humans MHC-Dependent?
Rapha?lle Chaix1,2*, Chen Cao3, Peter Donnelly1,4
1 Department of Statistics, University of Oxford, Oxford, United Kingdom,
2 Unité d'Eco-Anthropologie, CNRS UMR 5145, Musée de l'Homme, Paris, France,
3 CAS-MPG Partner Institute for Computational Biology, Shanghai, China,
4 The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
In several species, including rodents and fish, it has been shown that the Major Histocompatibility Complex (MHC) influences mating preferences and, in some cases, that this may be mediated by preferences based on body odour. In humans, the picture has been less clear. Several studies have reported a tendency for humans to prefer MHC-dissimilar mates, a sexual selection that would favour the production of MHC-heterozygous offspring, who would be more resistant to pathogens, but these results are unsupported by other studies. Here, we report analyses of genome-wide genotype data (from the HapMap II dataset) and HLA types in African and European American couples to test whether humans tend to choose MHC-dissimilar mates. In order to distinguish MHC-specific effects from genome-wide effects, the pattern of similarity in the MHC region is compared to the pattern in the rest of the genome. African spouses show no significant pattern of similarity/dissimilarity across the MHC region (relatedness coefficient, R = 0.015, p = 0.23), whereas across the genome, they are more similar than random pairs of individuals (genome-wide R = 0.00185, p<10−3). We discuss several explanations for these observations, including demographic effects. On the other hand, the sampled European American couples are significantly more MHC-dissimilar than random pairs of individuals (R = −0.043, p = 0.015), and this pattern of dissimilarity is extreme when compared to the rest of the genome, both globally (genome-wide R = −0.00016, p = 0.739) and when broken into windows having the same length and recombination rate as the MHC (only nine genomic regions exhibit a higher level of genetic dissimilarity between spouses than does the MHC). This study thus supports the hypothesis that the MHC influences mate choice in some human populations.
