Chongqing - The silkworm genome biology laboratory of Southwest University in Chongqing constructed the world’s first high-resolution pan-genome dataset representing almost the entire genomic content in the silkworm. These comprehensive silkworm genome resources will facilitate the basic research and precise breeding in silkworms and enlighten pan-genome studies on other species.

The enormously diverse phenotypes of silkworms are displayed throughout all developmental stages, from the eggs to larvae and pupae (including cocoons and pupae) and adults (clockwise from the northwest quadrant). (Photo provided to iChongqing)

The silkworm is an essential economic insect for producing silk. The currently available genomes limit understanding its genetic diversity and the discovery of valuable alleles for breeding.

Previously, only a single reference genome and partial re-sequencing data were available for silkworm gene research. Recently, the focus of genome research has shifted from a single reference genome to a pan-genome approach that provides more significant insights into the entire genomic content of a species.

The team has deeply re-sequenced 1,078 silkworms and assembled long-read genomes for 545 representatives distributed in all geographical regions of China, according to Tong Xiaoling, a professor at the silkworms genome biology laboratory at Southwest University.

The laboratory operation. (Photo provided to iChongqing)

With more than 600 mutation resources in the library, it becomes the complete sample library in three generations of pan-genome that can represent the genomic information of all silkworm taxa. These findings imply that it will be crucial for silkworm breeding in the future to explore and use these plentiful genetic resources.

Xiang Zhonghuai, an academician of the Chinese Academy of Engineering, pointed out that “researchers first regarded genetics as a breakthrough in the sericulture industry. In contrast, now we regard genomes as the starting point to revitalize the sericulture industry with science and technology in this century.”

(Chen Lu, as an intern, also contributed to the report.)