A collection of over 3,000 human cell lines, each with a mutation in a single gene, is reported this week in Nature Methods.This growing collection should provide a rich resource for functional studies of a variety of biological processes in human cells, such as signaling, metabolism, secretion or transcription.
Collections of single-gene knockout strains in model organisms are very useful for studying gene function. However, it is often also desirable to carry out such studies-especially on genes linked to disease-in a human experimental system.
To meet this need, Sebastian Nijman and colleagues describe a collection of human cells, which are genetically identical except that each has a mutation in a different single gene.The resource is built on a previously described cell line most of the genome of which is present in only one copy rather than the usual two copies in human somatic cells. This makes the otherwise time-consuming task of systematically mutating each gene much easier because only one copy must be targeted. The researchers used standard methods to achieve this for 3,396 genes, a third of the expressed genome in humans.