C57BL/6J-Mc1r^e/J

Stock number: 000060
Research areas: Dermatology Research, Endocrine Deficiency Research

Detailed description

On its original C57BL/6Ha genetic background, Mc1r^e homozygous adults have yellow coat color. They may exhibit some darker hairs (dorsally concentrated umbrous sootiness) when younger or prior to weaning, but they soon acquire an overall yellow coat with successive molts [Hauschka et al., 1968 J Hered (PMID:5713933)]. Furthermore, the yellow fur of homozygous mice results from an absence of eumelanin synthesis in the hair follicles. A small number of dark hairs can be found dorsally in homozygotes, and the animals have black eyes as well [Robbins et al., 1993 Cell (PMID:8458079)]. The appearance for Stock No. 000060 homozygous mice is expected to be similar.

C57BL/6-congenic mice with a similar spontaneous mutation Mc1r^e-J (Stock No. 003625) exhibit yellow coat color and black eyes as homozygotes, while heterozygous and wildtype mice exhibit black coat color and black eyes. The appearance for Stock No. 000060 heterozygous and wildtype mice is expected to be similar.

Development

The recessive yellow mutation (Mc1r^e) arose in 1963 in a C57BL/6Ha strain homozygous for Kit^w at Roswell Park Memorial Institute. By 1970 Dr. Elizabeth Russell had imported Mc1r^e on the C57BL/6Ha background into The Jackson Laboratory and began backcrossing it onto C57BL/6J. In 1974 the strain, maintained by backcross-intercross, had reached generation N8, in 1976 it reached generation N12, in 1978 it reached generation N18, and in 1979 it was cryopreserved at generation N20. The cryopreserved stocks were replenished in 2014 at generation N21F?pN1p (cryopreserved embryos from C57BL/6J oocytes fertilized by sperm from generation N21 homozygous males).

The Mc1r^e mutation is a frameshift due to a deletion of a single nucleotide at position 549. This mutation is predicted to result in a protein that continues out of frame for 12 amino acids before terminating. [PMID:8458079]

Allele

Symbol: Mc1r^e
Name: recessive yellow
MGI accession ID: MGI:1856028
Generation method: Spontaneous
Synonyms: e; MC1^-; Mc1r^-
Marker symbol: Mc1r
Marker name: melanocortin 1 receptor
Marker synonyms: CMM5; e; extension recessive yellow; Mcr1; MSH-R; Mshra; SHEP2
Chromosome: 8
Strain of origin: C57BL/6Ha
Molecular note: The mutation is a frameshift due to a deletion of a single nucleotide at position 549. This mutation is predicted to result in a protein that continues out of frame for 12 amino acids before terminating.