Article Text

Download PDFPDF
New linkage data for the X-linked types of muscular dystrophy and G6PD variants, colour blindness, and Xg blood groups
  1. Mayana Zatz*,
  2. Sueli B. Itskan,
  3. Ruth Sanger,
  4. O. Frota-Pessoa*,
  5. P. H. Saldanha


    Six families in which Duchenne muscular dystrophy (DMD) and G6PD or deutan colour blindness are segregating are reported. The sum of the lod-scores of these families together with three published previously indicates that the DMD locus is far from the G6PD:deutan cluster. The lod-scores of two families with Becker muscular dystrophy (BMD) informative for the G6PD locus together with those of one family previously studied by Emery, Smith, and Sanger (1969) suggest that the BMD locus could be at a measurable distance from this cluster. The maximum likelihood estimate of the recombination fraction is 0·27 and the 90% confidence limits are 0·17 and 0·40. This difference in linkage estimates for DMD and BMD suggests that the BMD and the DMD genes are located at two different loci on the X chromosome.

    Five more families with DMD and two with BMD informative for Xg blood groups support the conclusion of other authors that there is no hint of linkage between the loci for Xg and for the X-linked forms of muscular dystrophy.

    Statistics from

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


    • * Laboratório de Genética Humana, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil.

    • Laboratório de Genética Médica, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil.

    • MRC Blood Group Unit, Lister Institute, London, United Kingdom.