Epigenetics of insect polymorphism

许多昆虫表现出多态，从同一基因组产生不同的形式。这些例子包括蜜蜂中的蜂王和工蜂种姓的分化，以及蚜虫中有翅(有翼)和无翅(无翅)的变型的发育。为了研究多态发生的表观遗传学机制，分析了欧洲蜜蜂和豌豆蚜虫的全基因组甲基化图谱。在蜜蜂中，1,717个CpG位点在两个种姓之间被发现存在不同的甲基化。有趣的是，不同的甲基化基因包括几个性别决定基因，这意味着性别决定基因可能也参与了种姓分化。在蚜虫中，226个基因在两种形态之间发生了不同的甲基化。

Many insects exhibit polymorphism, producing different forms from the same genome. Such examples include queen and worker caste differentiation in honeybees and development of alate (winged) and apterous (non-winged) morphs in aphids. To investigate the epigenetic mechanisms underlying the occurrence of polymorphism, genome-wide methylation profiles were analyzed in the European honeybee, Apis mellifera, and in the pea aphids, Acyrthosiphon pisum. In the honeybee, 1,717 CpG sites were found to be differently methylated between the two castes. Interestingly, differently methylated genes included several sex-determining genes, implying that genes for sex determination might be also involved in caste differentiation. In the aphids, 226 were differently methylated between the two morphs.