祖父肥胖的儿孙更易受垃圾食品影响
科学网 · 2016/07/23
一项在小鼠身上开展的研究表明,肥胖雄性小鼠的“孙子”更容易遭受垃圾食品带来的有害健康影响。相关成果日前发表于《分子新陈代谢》杂志。

此项发现进一步证明,新的性状无须被永久记录在家庭基因中,便可在家族中传递下去。这种现象被称为表观遗传的隔代效应。

去年,一项研究发现,肥胖男性精子中的DNA在数百个位置被修改。同时,这些精子还含有短片段RNA。这些是表观遗传修饰,即它们不影响基因的精确编码,但可能影响特定基因的活性。

如今,来自澳大利亚悉尼张任谦心脏研究所的Catherine Suter及其团队研究了父亲肥胖产生的更长期影响。为此,他们将肥胖的雄性小鼠同瘦小的雌性小鼠交配。

研究发现,当被喂食垃圾食品时,同瘦小的雄性小鼠的后代相比,肥胖雄性小鼠的“儿子”和“孙子”都更有可能表现出脂肪肝疾病和糖尿病的早期迹象。相同的效应未在“女儿”或“孙女”身上看到。

即便是肥胖雄性小鼠的“儿子”被喂以健康饮食并且保持正常体重,它们的“儿子”在接触垃圾食品后,仍有更大的倾向患上同肥胖相关的疾病。不过,这种影响似乎不会传给“曾孙”。“这是好消息,因为它表明,肥胖循环能被打破。”Suter表示。


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