Silkworm gene bank approved in Chongqing

The National Genetic Resources Bank of the Silkworm in Chongqing — the first of its kind in China — was listed recently as one of 12 new genetic resource protection units for State-level livestock and poultry.

The Ministry of Agriculture and Rural Affairs approved the second group of units in January. Now, with the first batch released in 2021, there are 217 protection units, including 10 genetic resource banks in the country.

The official approval also confirmed the protection of China's silkworm genes — found in silkworm eggs — under the country's Animal Husbandry Law, according to the Institute of Sericulture and Systems Biology in Southwest University, the gene bank's home.

The gene bank, which was established in the 1930s, has maintained comprehensive silkworm data since 1940. Over the years, Chinese scientists such as Jiang Tongqing, the founder of China's silkworm experimental genetics; academician Xiang Zhonghuai, who is leading the silkworm genome study in China; and many young experts and scholars, have been devoted to the study of silkworms. The gene bank became world's biggest for domestic silkworms at the turn of the century, the university said.

The gene bank has kept more than 1,150 live genetic stocks of domestic silkworms, including local strains, improved varieties, natural mutants, chemical-induced and physically-induced artificial mutants, innovative germplasms that constructed via transgenic and genome-editing technique and special germplasms whose lineage traces to wild ancestors.

The stock covers more than 90 percent of the world's representative silkworm resources, according to the institute.

Notably, in September, the world's first super pan-genome map of the silkworm was completed by scientists at the university.

The genome map is believed to have the largest long-reads-based pan-genome of the world's plants and animals, as well as having the highest quality, said Dai Fangyin, director of the State Key Silkworm Laboratory at the university and the chief scientist of the National Sericulture Industry Technology System.

"The super pan-genome map of the silkworm will solve the breeding bottleneck and open up a new era for functional genomics and molecular breeding," said Xiang, the academician. "This is the biggest achievement in this domain in the past century."