| First Author | Lyon MF | Year | 1980 |
| Journal | Mouse News Lett | Volume | 62 |
| Pages | 49 | Mgi Jnum | J:13832 |
| Mgi Id | MGI:62011 | Citation | Lyon MF, et al. (1980) e locus alleles. Mouse News Lett 62:49 |
| abstractText | Full text of MNL contribution: 4. Dominance relationships at the Extension locus. von Lehhmann (MNL 48: 23 and MNL 50: 26-27) considered Etob as an incompletely dominant gene. He described Etob/Etob as black with agouti flanks and Etob/+ as darkened agouti. In our hands, however Etob would better be described as recessive. We have made crosses of Etob/+ x +/+ both on a homozygous agouti background, or on an Aa background by crossing Etob/+ AA x +/+ aa. In neither case was it possible to make a reliable classification of Etob/+ vs. +/+ among the offspring. We agree that there is a slight tendency for Etob/+ to be darker than +/+, but the difference is too slight for reliable distinction. Possibly the darkening seen by von Lehmann was due to the genetic background, since he mentions (MNL 50: 27) that another darkening factor was present in Mus poschiavinus (in which Etob was found). Similarly, in our hands Etob/+ cannot be distinguished from +/+ in the presence of Ay, although Etob/Etob Ay/+ is recognisable as a dark yellow. In crosses of Etob/Etob x Eso/+ the Eso/Etob offspring resembled Eso (i.e. there were two classes of offspring sombre Eso/Etob and wild-type Etob/+) and in backcrosses Eso/Etob x Etob/Etob the two classes of offspring could be distinguished by the agouti flanks of Etob/Etob. As found by von Lehmann, Etob is dominant over e and hence the dominance relationships are Eso > E > Etob > e. (Lyon and Jarvis) |
