A cheeky genome
Chinese hamsters are rodents that originated in the deserts of northern China and Mongolia. They are popular as pets throughout the world .
For decades, quite a few biotech drugs are produced by putting a gene for a protein into cells derived from the ovary of a Chinese hamster (CHO cell line), which then produce the protein. The history of CHO cells dates back to the 1950s, when ovarian connective tissue was harvested from the Chinese hamster and derivative cells spontaneously became immortal (Tjio, 1958). Since then, the host cells remain poorly characterized.
To facilitate CHO cell research and development, the community now relies on published draft genomes for the CHO-K1 cell line and several draft assemblies for the parent Chinese hamster. Today we share a chromosome-length upgrade to the assembly for the Chinese hamster published by Rupp et al., 2018. In order to do the upgrade, we used primary cells from the T.C. Hsu Cryo-Zoo at the University of Texas MD Anderson Cancer Center. The cells have been stored all the way back in 1977!
In agreement with previously published data, the chromosome-length assembly yielded 11 chromosomes (a very low chromosome number for a mammal!). See below how these gigantic chromosomes relate to those of other closely related rodents in the Cricetidae family (hamsters, voles, lemmings and New World rats and mice) we’ve recently assembled in the DNA Zoo: the golden hamster Mesocricetus auratus, shared here, and the canyon mouse Peromyscus crinitus, here!