西湖大学生命科学学院俞晓春等科学家在研究中取得进展。他们组装了小鼠Y染色体端粒到端粒完整序列（mT2T Y），填补了GRCm39参考基因组的所有缺口，并提供了完整的C57BL/6参考基因组。2026年9月10日出版的《科学》杂志发表了这项成果。

小鼠Y染色体对雄性生殖至关重要，但GRCm39参考基因组包含25个缺口，尤其是在重复和复杂区域。在此，研究人员从一只C57BL/6小鼠中组装了一个95.21 Mb的端粒到端粒Y染色体（mT2T Y），并整合了亲本基因组。该组装填补了所有缺口，纠正了结构错误，并为参考基因组增加了超过8.70 Mb此前未组装的序列。研究人员注释了142个此前未识别的基因，鉴定了Y特异性卫星阵列，并绘制了拟常染色体区（PAR）中的同源重组位点。对X-Y同源基因表达的分析揭示了一种Y染色体剂量补偿机制。通过将mT2T Y与T2T mhaESC结合，研究人员完成了所有C57BL/6染色体的T2T组装，命名为T2T mhaESC+Y，提供了一个完整的C57BL/6参考基因组。

附：英文原文

Title: The complete telomere-to-telomere sequence of a mouse Y chromosome

Author: Qilin Li, Junli Liu, Si Chen, Yixuan Hu, Dengfeng Li, Zhuojie Su, Yanxiao Zhang, Xiaochun Yu

Issue&Volume: 2026-09-10

Abstract: The mouse Y chromosome is essential for male reproduction, yet the GRCm39 reference contains 25 gaps, particularly in repetitive and complex regions. Here, we assembled a telomere-to-telomere Y chromosome (mT2T Y) of 95.21 Mb from a C57BL/6 mouse incorporating parental genomes. This assembly fills all gaps, corrects structural errors, and adds over 8.70 Mb of previously unassembled sequence to the reference genome. We annotated 142 previously unidentified genes, identified Y specific satellite arrays, and mapped homologous recombination loci in the pseudoautosomal region (PAR). Analysis of X Y homologous gene expression revealed a Y chromosome dosage compensation mechanism. By combining mT2T Y with T2T mhaESC, we completed the T2T assembly of all C57BL/6 chromosomes, designated T2T mhaESC+Y, providing a complete C57BL/6 reference genome.

DOI: 10.1126/science.aea2249

Source: https://www.science.org/doi/10.1126/science.aea2249