Mice homozygous for this recessive mutation are recognized by unkempt hair. At three weeks of age the phenotype is obvious and by five weeks of age the hair is less disheveled. Homozygous mice have no behavioral abnormalities, live normal life spans and breed normally.
The slck mutation arose spontaneously at The Jackson Laboratory in the recombinant inbred strain CXJ1/SalkJ in 1992. It was maintained on this background by sibling breeding until 2010 when an outcross was done to FVB/NJ followed by sibling intercrossing, and sperm was frozen from homozygous males at generation N1F2.