Zhen Huang, Zaoxu Xu, Hao Bai, Yongji Huang, Na Kang, Xiaoting Ding, Jing Liu, Haoran Luo, Chentao Yang, Wanjun Chen, Qixin Guo, Lingzhan Xue, Xueping Zhang, Li Xu, Meiling Chen, Honggao Fu, Youling Chen, Zhicao Yue, Tatsuo Fukagawa, Shanlin Liu, Guobin Chang, Luohao Xu
Microchromosomes are prevalent in nonmammalian vertebrates [P. D. Waters et al. , Proc. Natl. Acad. Sci. U.S.A. 118 (2021)], but a few of them are missing in bird genome assemblies. Here, we present a new chicken reference genome containing all autosomes, a Z and a W chromosome, with all gaps closed except for the W. We identified ten small microchromosomes (termed dot chromosomes) with distinct sequence and epigenetic features, among which six were newly assembled. Those dot chromosomes exhibit extremely high GC content and a high level of DNA methylation and are enriched for housekeeping genes...
February 21, 2023: Proceedings of the National Academy of Sciences of the United States of America