Mammalian chimaeras / Anne McLaren.

  • McLaren, Anne.
Date:
[1976]
Catalogue details

Licence: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)

Credit: Mammalian chimaeras / Anne McLaren. Source: Wellcome Collection.

    63/168 (page 53)
    Hair 53 (iJ) (h) U) Fig. 19. Hair shafts from (a) an agouti hair (C3H x C57BL F,), (h) a cream hair (multiple recessive, dd bb aa pp c'^'' (c) a chimaera. The septa in the chimaera hair vary in the amount of melanin pigment they contain, from none as in the multiple recessive, to the full amount of the agouti component. of studies with chimaeras, that at least one gene at the Mottled\oc\xs may act independently through melanocytes and hair follicle cells. In general, however, genes affect one cell population or the other, but not both. As we shall see later, 'melanocyte chimaeras' present a very different appearance from 'hair follicle chimaeras' from the point of view of the coat colour pattern. Microscopic examination has shown that chimaerism may extend to the level of the individual hairs (McLaren & Bowman, 1969). In chimaeras be¬ tween a pigmented and a non-pigmented strain the shafts of some hairs were fully pigmented, others lacked pigment entirely, and others again were patchy, with adjacent septa differing widely in the amount of pigment they contained (Fig. 19). Various degrees of intermediate expression were also seen in the hairs of agouti<->non-agouti chimaeras, corresponding presumably to hair follicles with different proportions of the two component genotypes. The