The turquoise killifish is a small freshwater African fish and a model organism for studying aging. Now researchers will be able to observe the changes in individuals of this species (Nothobranchius furzeri) much more easily, as a German team has used CRISPR to inactivate three genes in one go, causing their vibrant pigmentation to disappear.

The transparent line, dubbed Klara, was presented on eLife, which also released this video on twitter. The idea is not new, in fact crystal-clear mutants of zebrafish and medaka already swim around in laboratories. But Klara is a valuable new arrival, especially for aging scientists. In fact, despite living only a few months to about a year, these fish show typical signs of mammalian aging including telomere shortening.