美国哈佛大学Hopi E. Hoekstra团队发现染色体倒位导致鹿鼠生态型之间多种性状的差异。这一研究成果于2022年7月22日发表在国际顶尖学术期刊《科学》上。

利用鹿鼠（Peromyscus maniculatus）的森林和草原生态型，他们描述了两个决定性特征（尾巴长度和毛色）变异的遗传基础，并发现了与两者相关的41兆碱基染色体倒位。暗色长尾森林生态型的反转频率为90%，在栖息地过渡期间减少，并且在轻短尾草原生态型中不存在。尽管基因流动水平很高，但他们将发散选择与在野外观察到的频率保持倒置关联起来，并探索因倒置中抑制重组而产生的适应性益处。他们揭示了在经典哺乳动物生态型的进化和维持中，以前未表征的大型倒置的关键作用。

据介绍，如何在一个物种中建立和维持适应当地的生态型是进化生物学中一个长期存在的问题。

附：英文原文

Title: A chromosomal inversion contributes to divergence in multiple traits between deer mouse ecotypes

Author: Emily R. Hager, Olivia S. Harringmeyer, T. Brock Wooldridge, Shunn Theingi, Jacob T. Gable, Sade McFadden, Beverly Neugeboren, Kyle M. Turner, Jeffrey D. Jensen, Hopi E. Hoekstra

Issue&Volume: 2022-07-22

Abstract: How locally adapted ecotypes are established and maintained within a species is a long-standing question in evolutionary biology. Using forest and prairie ecotypes of deer mice (Peromyscus maniculatus), we characterized the genetic basis of variation in two defining traits—tail length and coat color—and discovered a 41-megabase chromosomal inversion linked to both. The inversion frequency is 90% in the dark, long-tailed forest ecotype; decreases across a habitat transition; and is absent from the light, short-tailed prairie ecotype. We implicate divergent selection in maintaining the inversion at frequencies observed in the wild, despite high levels of gene flow, and explore fitness benefits that arise from suppressed recombination within the inversion. We uncover a key role for a large, previously uncharacterized inversion in the evolution and maintenance of classic mammalian ecotypes.

DOI: abg0718

Source: https://www.science.org/doi/10.1126/science.abg0718