Tight-skin (Tsk) maps on mouse chromosome 2 within the region of linkage homology with human chromosome 15.

The tight-skin (Tsk) mutation has been mapped to mouse chromosome 2 between the visible markers pallid (pa) and agouti (a). The phenotype observed in Tsk heterozygotes includes a thickened dermis that is tightly adherent to underlying tissues, increased production of collagen and other matrix proteins in the dermis, an enlarged heart, overgrowth of bones, scoliosis, and emphysematous lungs. Although it is known that the mutation is semidominant and that homozygous Tsk/Tsk mice die at 7 or 8 days in utero, the actual defect leading to the distinct heterozygous and homozygous phenotypes is unknown. To facilitate the positional cloning of Tsk, an interspecific backcross between C57BL/6J Tsk/+ and Mus spretus has been conducted. Our data link Tsk to cloned genetic markers and indicate the order pa-B2m-Tsk-Fbn-1-II-1a-a.