A Small Deletion Hotspot in the Type II Keratin Gene<i>mK6irs1/Krt2-6g</i>on Mouse Chromosome 15, a Candidate for Causing the Wavy Hair of the Caracul (<i>Ca</i>) Mutation

The study identified the mK6irs1/Krt2-6g gene on mouse chromosome 15 as a strong candidate for causing the wavy hair mutation known as caracul (Ca) in mice. This mutation was found to be autosomal dominant and independent of a transgenic insertion. Researchers discovered that mutations in this gene consistently occurred in conserved positions of the α-helical rod domain, with four alleles sharing an identical amino acid deletion (N 140 del) and a fifth allele having a substitution (A 431 D). An additional allele induced by ENU mutagenesis also showed a substitution (L 424 W). These findings suggested a mutation hotspot in the Ca locus and provided insights into the genetic pathway for hair formation, potentially implicating this gene in human hair and skin diseases.