They certainly aren't perfect proxies for humans, but they have a lot of advantages: 1) They reproduce quickly. 2) We have inbred several different strains so t

They certainly aren't perfect proxies for humans, but they have a lot of advantages: 1) They reproduce quickly. 2) We have inbred several different strains so that every member is genetically identical to all the others of the same sex. 3) There is a huge amount of scientific knowledge already accumulated on mice, and the inbred strains specifically. Different developmental checkpoints, what healthy looks like across basically every dimension. These first two make it possible to do repeatable studies at relatively low costs. The latter allows you to do things like knock out or replace a gene and see see what impacts it has biologically and you can find out in weeks instead of years. Research mice the way biologists reduce their build times.