Strain Detail Sheet

Phenotype:
The albino (Tyr) locus encodes the rate-limiting enzyme for pigmentation, which is TYROSINASSE. The absolute requirement for functional TYROSINASE to catalyze the formation of melanin pigment is illustrated by the phenotypes of mice that lack this locus as a result of deletion, for example mice heterozygous for two overlapping deletions, MMRRC:009964 and MMRRC:009965, in which the albino locus is absent. The mice also lack all melanin pigment. Vertebrates that lack normal tyrosinase are characterized by reduction or absence of pigmentation in the eyes and/or skin. If the reduction of pigmentation is severe, optic nerve development may be abnormal, resulting in blindness. Reduction of melanogenesis may result from failure of normal tyrosinase function caused by its abnormal interaction with other proteins, from defects in its regulatory region, from absence or defect of the structural gene. The series of natural mutations that affect availability of normal tyrosinase function includes mutants of this type. C57BL/6J-Tyr^c-2J/Tyr^c-2J, available at The Jackson Laboratory, lacks tyrosinase activity as a result of point mutation in the structural region of the gene. MMRRC:000140 may have reduced pigmentation resulting from a temperature sensitivity that affeects the TYROSINASE, which functions more effectively in the cooler parts of the body. MMRRC:000141 seems to have nearly normal pigmentation in the eyes, but their hair pigmentation is a uniform gray. In MMRRC:000139 the eye pigmentation is somewhat reduced, but intense, while the hair is unpigmented. MMRRC:000144 mice are very dark, nearly black. Mutant alleles in MMRRC:000145 and MMRRC:000142 result in chimerism of hair and eye pigmentation that has been attributed to a rearrangement of the DNA 5kb upstream of the tyrosinase locus. One of the genes that regulates the activity of TYROSINASE is MITF. And there are functional interactions between TYROSINASE and TYROSINASE-RELATED PROTEIN within the pigment cell.

Chinchilla mice are eumelanic and very dark, nearly the full intensity of black, but if they are chinchilla and pheomelanic, their pigmentation is a low intensity, nearly white. This difference is also true in most (not all) other mice that are mutant at the albino locus.

Mammalian Phenotype Terms:
      assigned by genotype

The following phenotype information may relate to one or more alleles on a genetic background differing from this MMRRC strain.

Tyr^c-ch/Tyr^c-ch

• pigmentation phenotype
• diluted coat color (MGI Ref ID J:6611)
• mice have a grey coat color
• the amount of melanin found in anagen hairbulbs is reduced by more than 30% compared to wild-type mice
• skin/coat/nails phenotype
• diluted coat color (MGI Ref ID J:6611)
• mice have a grey coat color
• the amount of melanin found in anagen hairbulbs is reduced by more than 30% compared to wild-type mice

Strain Type: Congenic

Founder genetic background: STOCK

Strain genetic background: B6.Cg

Strain Development:
These mice were backcrossed onto C57BL/6J by DeWayne Townsend, who sent them to Lamoreux in 1993. They were subsequently maintained by intercrossing and occasional backcrosses onto C57BL/6J.

• Albinism
• Development of optic nerve
• Visual Defects (Blindness)
• Genetic Controls over Pigmentation of Eyes and Skin
• Failure of Melanogenesis
• Neural Crest Development

Donor: Lynn Lamoreux, Ph.D., Texas A&M University

Primary Reference:

Townsend D, Witkop CJ Jr, Mattson J. Tyrosinase subcellular distribution and kinetic parameters in wild type and C-locus mutant C57BL/6J mice. J Exp Zool. 1981 Apr;216(1):113-9. (Medline PMID: 6793688 )

Lamoreux ML, Woolley C, Pendergast P. Genetic controls over activities of tyrosinase and dopachrome conversion factor in murine melanocytes. Genetics. 1986 Aug;113(4):967-84. (Medline PMID: 3091449)

* Additional charges may apply for any special requests. Shipping costs are in addition to the basic distribution/resuscitation fees. Information on shipping costs and any additional charges will be provided by the supplying MMRRC facility.

Click button to Request this one strain. (Use the MMRRC Catalog Search to request more than one strain.)
MMRRC Item # Description	Distribution Fee/unit (US $)	Units	Notes
000144-MU-RESUS Litter recovered from cryo-archive	$2,022.00 Non-Profit $4,109.00 For-Profit	Litter	Recovered litter1; additional fees for any special requests.
000144-MU-SPERM Cryo-preserved spermatozoa	$437.00 Non-Profit $817.00 For-Profit	Aliquot	Approximate quantity.2
000144-MU-EMBRYO Cryo-preserved embryos	$1,038.00 Non-Profit $2,621.00 For-Profit	Aliquot	Approximate quantity3: 20-40 embryos / aliquot

¹ The distribution fee covers the expense of resuscitating mice from the cryo-archive; you will receive the resulting litter. The litter will contain at minimum one breedable mutant carrier; the actual number of animals and the gender and genotype ratios will vary. (Typically, multiple breeder pairs can be established from the recovered litter.) Prior to shipment, the MMRRC will provide information about the animals recovered. If you anticipate or find that you need to request specific genotypes, genders or quantities of mice in excess of what is likely from a resuscitated litter, you may discuss available options and pricing with the supplying MMRRC facility.

² An aliquot contains sufficient material (volume and concentration) for at least two IVF or several artificial inseminations (based on our procedures). The MMRRC makes no guarantee concerning success of these procedures when performed outside the MMRRC facilities.

³ An aliquot contains a sufficient number of embryos (in one or more vials and based on the transfer success rate of the MMRRC facility) to transfer to at least two recipients. The MMRRC makes no guarantee concerning embryo transfer success experienced in the recipient investigator's laboratory. Neither gender nor genotype ratios are guaranteed.