2026年8月27日，中国科学院昆明动物研究所施鹏等科学家在《科学》发表研究，揭示了基因组倾向性与性染色体演化方向之间的关联。

性染色体演化是脊椎动物中最具动态性的基因组创新之一，但为何一些谱系演化出XY型而另一些则演化出ZW型，仍不清楚。通过对19种壁虎的染色体级别基因组分析，研究人员发现壁虎的性染色体分别从16条祖先染色体独立起源。它们的起源在时间和方向上均非随机。在11个可确定年代的起源中，有5个集中在中中新世气候转型期（约1000万年前）附近。祖先基因含量与演化方向相关——睾丸富集区域倾向于演化为ZW型，而睾丸贫乏区域倾向于演化为XY型，这一模式在多个羊膜动物性染色体起源中均有观察到。具有遗传性别决定系统的壁虎，通过异配性别中上调表达的方式反复演化出部分剂量平衡。因此，性染色体演化受到祖先基因组倾向性和环境背景的约束。

附：英文原文

Title: Genomic predisposition is associated with the direction of sex chromosome evolution

Author: Yang Zhou, Jiazheng Jin, Chuan Jiang, Olga Dudchenko, Brendan J. Pinto, Zane Colaric, Ruqayya Khan, Arina D. Omer, Xuemei Li, Zhenzhen Song, Li Han, Wanyi Chen, Lichun Jiang, Zhangyue Song, David Weisz, Yun Xia, Yin Qi, Zhengqing Cao, Yudian Peng, Zexian Zhu, Qi Zhou, Yan Liu, Xiaosong Gu, Stuart V. Nielsen, Aaron H. Griffing, Tariq Ezaz, Arthur Georges, Ian Brennan, Erez Lieberman Aiden, Tony Gamble, Peng Shi, Guojie Zhang

Issue&Volume: 2026-08-27

Abstract: Sex chromosome evolution is among the most dynamic genomic innovations in vertebrates, yet why some lineages evolve XY while others evolve ZW remains unclear. Using chromosome-level genomes from 19 geckos, we found that gecko sex chromosomes originated independently from 16 ancestral chromosomes. Their origins are nonrandom in both time and direction. Five of 11 datable origins coincide near the Middle Miocene Climatic Transition (~10 million years ago). Ancestral gene content is associated with the direction of evolution, with testis-enriched regions tending to evolve into ZW and testis-depleted regions into XY, a pattern observed across multiple amniote sex chromosome origins. Geckos with genetic sex determination repeatedly evolve partial dosage balance through up-regulation in the heterogametic sex. Sex chromosome evolution thus follows constraints from ancestral genomic predisposition and environmental context.

DOI: 10.1126/science.aec3449

Source: https://www.science.org/doi/10.1126/science.aec3449