C57BL/6JRj Mouse

This strain was created by C.C. LITTLE, in 1921, from Miss Abbie LATHROP’s stock.
The Jackson Laboratory’s colony was divided in two sub-strains before 1937, resulting in the C57BL/6 and the C57BL/10 strains. The C57BL/6 strain was brought to The Jackson Laboratory in 1948 (C57BL/6J).

It’s a widely used strain and was the first one to have its genome sequenced. It’s not very sensitive to spontaneous tumours but allows for the expression of a wide variety of mutations, hence its frequent use as genetic background in transgenic models.

C57BL/6JRj show age-related hearing loss and are resistant to audiogenic seizures. It is sensitive to Diet-Induced Type II diabetes and atherosclerosis.

C57BL/6JRj can show alopecia of uncertain etiology: it could have behavioural causes – overgrooming/barbering (JAX® Notes, 1987, Sundberg et al., 2011) – or behaviour similar to human compulsive hair pulling (Garner et al., 2004).

C57BL/6JRj are also characterized by hereditary hydrocephalus (1 to 4% incidence), imperforate vagina after 24 to 28 days), low bone density, higher rates of malocclusion, high rates of microphtalmia and ocular malformations and addiction to morphine and alcohol.

C57BL/6JRj carry a deletion in the Nnt gene (arose in the C57BL/6J prior to 1984).

C57BL/6JRj are active and relatively aggressive but easy to manipulate and have a long life expectancy (2 years).

Main application and research fields