Murphy Roths large (MRL/MpJ) is a strain of laboratory mouse developed in 1999 at The Wistar Institute in Philadelphia, Pennsylvania.[1] Originally bred for autoimmune disease research, it was discovered to have remarkable tissue regeneration abilities.[2][3][4]
The MRL/MpJ mouse strain was selectively bred by scientists to have an autoimmune genetic disorder (retained through inbreeding) to be used as a model for autoimmune disease research.[1] After making puncture wounds in their ears, these mice were observed to completely regenerate from these wounds without development of scar tissue.[1][2] In further research, this mouse strain has been observed to have the ability to also regenerate cardiac tissue, displays a resistance to muscle dystrophy, and is resistant to experiencing hyperglycemia from a diet high in fats.[5][6][7]