PDF(Pubmed)
Abstract：
Gut microbiomes of mammals carry a complex symbiotic assemblage of microorganisms. Feeding newborn infants milk from the mammary gland allows vertical transmission of the parental milk microbiome to the offspring\'s gut microbiome. This has benefits, but also has hazards for the host population. Using mathematical models, we demonstrate that biparental vertical transmission enables deleterious microbial elements to invade host populations. In contrast, uniparental vertical transmission acts as a sieve, preventing these invasions. Moreover, we show that deleterious symbionts generate selection on host modifier genes that keep uniparental transmission in place. Since microbial transmission occurs during birth in placental mammals, subsequent transmission of the milk microbiome needs to be maternal to avoid the spread of deleterious elements. This paper therefore argues that viviparity and the hazards from biparental transmission of the milk microbiome, together generate selection against male lactation in placental mammals.
摘要：
哺乳动物的肠道微生物群携带复杂的微生物共生组合。从乳腺喂养新生婴儿的牛奶可以将亲代牛奶微生物组垂直传播到后代的肠道微生物组。这有好处,但对宿主人口也有危害。使用数学模型，我们证明，双亲垂直传播使有害的微生物元素入侵宿主种群。相比之下,单亲垂直传播充当筛子，阻止这些入侵。此外，我们表明，有害的共生体会对宿主修饰基因产生选择，从而使单亲传播保持不变。由于胎盘哺乳动物在出生时发生微生物传播，牛奶微生物组的后续传播需要是母体的，以避免有害元素的传播。因此，本文认为，胎生性和牛奶微生物组的双亲传播的危害，在胎盘哺乳动物中共同产生针对雄性泌乳的选择。
