One of the most used inbred mouse models, the C57BL/6 is used in nearly every research application, and it's commonly used as the genetic background for transgenic mouse models. It is also the preferred model for studying diet-induced obesity and the chronic experimental autoimmune encephalomyelitis model of multiple sclerosis.
Popular research applications include oncology
immunology, metabolic disease, addiction and toxicology
C57BL/6NTac is the preferred C57BL/6 substrain for generation of genetically engineered models, including by the Knockout Mouse Project (KOMP) and International Mouse Phenotyping Consortium (IMPC)
The Black 6 has superior reproductive performance compared to other B6 substrains: superovulated females yield a high number of embryos and males have higher sperm fertilization rates
The C57BL/6NTac has proven more amenable to the development of quality embryonic stem cells compared to other B6 substrains
Popular strain for syngeneic tumor experiments; with a suite of related strains on the same background for mechanistic studies including Rag2, Rag2/OT-I, Rag2/OT-II and many more
The C57BL strain created by C.C. Little in the 1920's gave rise to the C57BL/6 and C57BL/10 substrains sometime before 1937.