食物的寻找、选择和消化之间存在一定的关系，虽然宏观上的主观判断存在合理性，但缺乏遗传学上的直接证据。
中国科学院昆明动物研究所张亚平院士，吴东东博士，David Irwin教授等研究人员分析了12种果蝇中六个和食物有关的基因家族：类胰蛋白丝氨酸蛋白酶(Tryp_SPc)（主要作用于食物消化）；气味结合蛋白(odorant-binding protein, OBP)，嗅觉受体(OR)，味觉受体(gustatory receptor，GR) （对于寻找、选择鉴定食物，避免有毒物质是必不可少的）；细胞色素P450 (cytochrome P450, CYP450) 和谷胱甘肽-S-转移酶基因(glutathione S-transferase, GST) （是食物中以及代谢过程中产生的有毒物质的解毒酶），发现这些基因家族的大小在12个果蝇基因组中存在显著相关性。考虑到这些基因家族中的很多基因在食物寻找、选择和消化过程中都起到重要作用，推测该六个基因家族由于食物的适应性在果蝇进化过程中发生了相关性进化。
该研究结果发表在著名杂志Genome Biology and Evolution上。（生物谷Bioon.com）
生物谷推荐原文出处：
Genome Biol Evol (2011) doi: 10.1093/gbe/evr034
Correlated evolution among six gene families in Drosophila revealed by parallel change of gene numbers
Dong-Dong Wu1, David M. Irwin1,3,4 and Ya-Ping Zhang1,2,*
Abstract
Proteins involved in a pathway are likely to evolve in a correlated fashion, and coevolving gene families tend to undergo complementary gains and losses. Accordingly, gene copy numbers (i.e. repertoire size) tend to show parallel changes during the evolution of coevolving gene families. To test and verify this hypothesis, here we describe positive correlations among the repertoire sizes of six gene families, i.e., trypsin-like serine protease, odorant-binding protein, odorant receptor, gustatory receptor, cytochrome P450 and glutathione S-transferase after excluding the possibility of phylogenetic constraint and random drift. The observed correlations are indicative of parallel changes in the repertoire sizes of the six gene families that are due to similar demands for the quantity of these different genes in different lineages of Drosophila. In conclusion, we propose that the correlated evolution among these six gene families in Drosophila is a signature of a parallel response to ecological adaptation.
