A pleiotropic gene which controls coat color and lethality in early development in the mouse

Bh (black at hatch) gene appears to be expressed in melanocytes of feather germs in the Japanese quail (Coturnix coturnix japonica)

The Bh (black at hatch) gene was examined to determine whether it is expressed in plumage melanocytes by analyzing pigmentation patterns of Bh melanocytes placed in the micro-environment of the feather germs of quail embryos with pink eyes. These host quails genetically lack a large part of plumage melanin. The Bh locus in these almost white quails is wild-type. When Bh neural crest cells were transplanted orthotopically into the host embryos, wild-type and Bh/+ melanocytes, which differentiated from the transplanted neural crest cells, formed plumage pigmentation patterns characteristic of each genotype in the micro-environment of the host feather germs. Brown plumage pigmentation, which was very similar to that of 10-day Bh/Bh embryos, was also observed in the feather germs of host embryos that received Bh neural crest cells, although the genotype of the donors could not be determined. These donors died before pigmentation of their feather germs occurred. The results demonstrate that pigmentation patterns of Bh melanocytes are not altered in the micro-environment of the host germs, suggesting that the Bh gene is autonomous in Bh melanocytes and is expressed in melanocytes of both Bh and the host feather germs, and that it causes the normal pigmentation pattern to be altered.