FAMILIAL X-LINKED MENTAL-RETARDATION, VERBAL DISABILITY, AND MARKER X CHROMOSOMES

  • 1 January 1979
    • journal article
    • research article
    • Vol. 31  (2) , 214-222
Abstract
Cytogenetic and verbal studies were done on members of 4 families with nonspecific X-linked mental retardation. Cytogenetic analysis was done using media 199 and GTG[Giemsa bands by trypsin using Giemsa]-banding; one family had a marker X with a fragile site in band Xq27 or 28. Preliminary results indicate variation of culture conditions can effect the frequency of the marker X. A generalized language disability was found which tended to concentrate in the areas of auditory reception, auditory sequential memory, visual closure and grammatic closure. Articulation errors involved the same sounds which are late in normal development and occur most frequently in the general population and a Down syndrome population.