| First Author | Beechey CV | Year | 1986 |
| Journal | Mouse News Lett | Volume | 75 |
| Pages | 28 | Mgi Jnum | J:14096 |
| Mgi Id | MGI:62273 | Citation | Beechey CV, et al. (1986) Mutations at the Sp locus. Mouse News Lett 75:28 |
| abstractText | Full text of MNL contribution: 6. Mutations at the Sp locus. Three splotch mutants, Sp<1H>, Sp<2H> and Sp<3H> have been recovered in specific locus experiments. The first two appeared after paternal 5 Gy + 5 Gy (24 h interval) acute X-irradiation with spermatogonial sampling. One was found as a cluster of 2 mutations and behaves like a repeat of the original Sp mutation, with ventral white spotting, often extending to the feet and tail, in the heterozygote, and rachischisis and other abnormalities in lethal homozygotes and in crosses to Sp. The second was similar, except that its coat tended to be somehat light also but its penetranoe was only about 50%. Sp<3H> was recovered after maternal X-irradiation with 6 Gy. It is distinguished from Sp by (i) its consistent growth retardation, which becomes obvious soon after birth and persists with adult life, (ii) occasional presence of head dots or tail-kinks, ( iii) occasional absence of ventral spotting. Although crosses to Sp give some abnormal embryos with rachischisis, cranioschisis and abnormal tails, no extra lethality or abnormality has been found in 44 implants from Sp<3H>/+ intercross openings. This suggests that the homozygote may well die before implantation. It seems likely that Sp<3H> is a deletion covering this locus. It is proposed to call it retarded splotch, with symbol Sp<r>. (Beechey and Searle) |
