Hereditary disorders of erythrocyte metabolism : proceedings of the symposium held February 13-15, 1967, at the City of Hope Medical Center, Duarte, California / edited by Ernest Beutler.

Date:
[1968]
Catalogue details

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

Credit: Hereditary disorders of erythrocyte metabolism : proceedings of the symposium held February 13-15, 1967, at the City of Hope Medical Center, Duarte, California / edited by Ernest Beutler. Source: Wellcome Collection.

    28/364 (page 12)
    12 HEREDITARY DISORDERS OF ERYTHROCYTE METABOLISM + PGM^ PGM^ PGM', PGM^ PGM' PGM', PGM] PGM^ PGMj PGM¡ PGM¡ PGM] PGMj FIG. 11. Diagram showing phosphoglucomutase isoenzymes determined by different alleles at the three loci, PGMi, PGMi, and PGM3. Thus it appears that at least three different genetic loci determine phospho¬ glucomutase. The isoenzymes thought to be attributable to different alleles at each of these three loci are illustrated diagrammatically in Figure 11. An individual homozygous at all three loci shows at least eight distinct phospho¬ glucomutase isoenzymes. The patterns will be even more complex in individuals heterozygous at one or more of the loci, and it is clear that a very large number of different combinations of phosphoglucomutase isoenzymes are pos¬ sible in different individuals. The relative frequencies with which these occur will of course depend on the gene frequencies. Typical values for the common alleles in various populations are shown in Table 3. Figure 11 illustrates rather clearly two very striking features of phospho¬ glucomutase variations. One is that each allele appears to affect the electro- TABLE 3. Gene frequencies of common alleles at the three phosphoglucomutase loci; PGMi, PGM2, and PGMj {Data on PGM¡ and PGM2 from Hopkinson and Harris')