Allan-Herndon syndrome. II. Linkage to DNA markers in Xq21

Am J Hum Genet. 1990 Sep;47(3):454-8.


The original family with the Allan-Herndon type of X-linked mental retardation has been investigated for linkage by using DNA probes spanning the length of the X chromosome. Available for study, over 3 generations, were 13 affected males, three obligate carriers, and three normal sons of the obligate carriers. Initial disease-to-marker analysis suggested linkage to three markers (DXYS2 [7b], DXS250 [GMGX22], and DXS3 [p19-2]) located in Xq21. All three exhibited the same maximum lod score of 2.3 at a maximum theta of .05. Multipoint analysis using LINKMAP and a set of four DNA markers (DXYS1-DXYS2-DXS3-DXS94) gave a multipoint lod score of 3.58 for a location of the Allan-Herndon syndrome near locus DXYS1 (pDP34). Therefore, our data indicate that the gene for the Allan-Herndon syndrome is likely located in Xq21.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Multiple / genetics*
  • DNA Probes
  • Face / abnormalities
  • Female
  • Genetic Linkage*
  • Genetic Markers
  • Humans
  • Intellectual Disability / genetics*
  • Lod Score
  • Male
  • Muscular Diseases / genetics*
  • Pedigree
  • Syndrome
  • X Chromosome*


  • DNA Probes
  • Genetic Markers