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.

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    134 Perspectives for advantageous traits, involving heterozygosity at numerous loci, as has been done in plant breeding. A single meiotic event, with its resultant multiple recombination, would destroy many years' work in building up the optimal genome. Yet there might be circumstances in which it was desired to combine two such genomes in the same individual, perhaps to exploit vegetative heterosis if such a phenomenon exists, perhaps just to see how two sets of characters would combine together as a guide to whether it would be worth bringing them together genetically. Chimaerism would provide the obvious means, allowing genomes to be combined without the necessity for meiosis. An analogous situation already exists in plants, where highly selected plant varieties are often propagated by vegetative means alone, to avoid meiosis and recombination, and where 'graft hybridization' is a standard procedure for combining valuable traits within a single individual. Such procedures applied to animals are still, however, in the realms of science fiction. The importance of chimaeras in science today lies in their use as an analytical tool in experimental embryology and developmental genetics. I have tried in this book to give an account of what has been done so far: I hope I have also given some impression of how much is still waiting to be done. Note added in proof For use of chimaeras to 'rescue' a sterile genotype (T/m/Y), see: Lyon, M.F., Glenister, P.H. & Lamoreux, M.L. (1975). Normal sperma¬ tozoa from androgen-resistant germ cells of chimaeric mice and the role of androgen in spermatogenesis. Nature, bond. 258, 620-2. For the integration of tumour cells (i.e. teratocarcinoma) into normal embry¬ onic development by the injection chimaera technique, see: Papaioannou, V.E., McBurney, M.W., Gardner, R.L. & Evans, M.J. (1975). Fate of teratocarcinoma cells injected into early mouse embryos. Nature, Lond. 258, 70-2. Mintz, B. & Illmensee, K. (1975). Normal genetically mosaic mice pro¬ duced from malignant teratocarcinoma cells. Proc. Nat. Acad. Sci., USA 72, 3585-9.