▶ Proper name

Hos:HR-1

▶ Description

Homozygous mutants (Hr^hr/Hr^hr) show normal development of the first hair coat (first hair cycle). Starting at 2 weeks of age, they lose their hair coat rapidly and completely due to an abnormal second hair cycle [1, 2]. At weaning (~3 weeks of age), they are completely hairless [3].

▶ Appearance

albino, without hair, unaffected

▶ Genotype

Hr^hr/Hr^hr
an insertion mutation in intron 6 of mutant Hr genes [3]

▶ Reseach

* dermatology, wound healing model, safety and efficacy testing
* scratching response of hairless mice with atopic dermatitis-like dry skin → HR-AD diet
* inflammatory acne mouse model [4]
* photochemical skin micronucleus test [5]
* photochemical genotoxicity [5]
* In vivo bioluminescence imaging [6]

▶ Development

The hairless mutation (Hr^hr) was found at Sandra Biological Supply in New York City in 1968. It was brought to Temple University and crossed to CBA mice. These mice were named Skh:HR. We received non-alvino Skh:HR mice and generated homozygous albino animals that are segregating for the hairless phenotype. We named these mice Hos:HR-1.

▶ Attention

Breeding is prohibited.

▶ References

[1] Brooke, H.C. 1926. Hairless mice. J. Hered. 17, 173–174.
[2] Sundberg, J. P. & King, L. E. Morphology of hair in normal and mutant laboratory mice. Eur. J. Dermatol. 11, 357–61
[3] Suzuki, O., Koura, M., Noguchi, Y., Uchio-Yamada, K. & Matsuda, J. Zygosity determination in hairless mice by PCR based on Hr(hr) gene analysis. Exp. Anim. 62, 267–73 (2013).
[4] Jang, Y. H., Lee, K. C., Lee, S.-J., Kim, D. W. & Lee, W. J. HR-1 Mice: A New Inflammatory Acne Mouse Model. Ann. Dermatol. 27, 257–64 (2015).
[5] Hara, T. et al. In vivo photochemical skin micronucleus test using a sunlight simulator: detection of 8-methoxypsoralen and benzo[a]pyrene in hairless mice. Mutat. Res. 631, 1–8 (2007).
[6] Nakanishi, T. et al. Bioluminescence imaging of bone formation using hairless osteocalcin-luciferase transgenic mice. Bone 51, 369–375 (2012).