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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    18 Techniques {<г) i « л А ^ ^ ^ ^ вь . ^ ** -► , -I (с) Fig. 8. Metaphase plates from the bone marrow of a CBA XX/XY chimaera, in which the XY component carried two T6 marker chromosomes, (a) and (c) show CBA-T6T6 male plates, each with a Y chromosome (long arrow), the two shortest autosomes (short arrows), and two even smaller T6 marker chromosomes, (b) and (d) show CBA-p plates of female genetic sex, with no chromosomes smaller than the two shortest autosomes (arrowed). From Mystkowska & Tarkowski (1968). portions of the two components in a variety of different tissues. The variant used most widely for this purpose is the T6 chromosome translocation (Fig. 8): strains homozygous for the translocation have two small 'marker' chromosomes, while heterozygotes have a single such chromosome (see e.g. Mystkowska & Tarkowski, 1968; Ford, Evans & Gardner, 1975¿). Variations between strains in the amount of pericentric heterochromatin on certain chromosome pairs, visualized by Giemsa staining (Fig. 9), have been similarly used (McLaren, 1975«), and in the special case of XX/XY chimaeras, chromo¬ somal sexing with the aid of either Giemsa staining or autoradiographic detection of the Y chromosome (Fig. 10) provides yet another means of dis¬ criminating one component from another (McLaren, 1972c). Chromosomal techniques have two major disadvantages: they cannot be used on histological sections, so cannot provide any information on cell localization within tissues, and they can be applied only to cells undergoing