Article

Genetic linkage analysis of the X chromosome in autism, with emphasis on the fragile X region

Developmental Psychiatry Section, University of Cambridge, Cambridge, England, United Kingdom
Psychiatric Genetics (Impact Factor: 2.27). 07/2005; 15(2):83-90. DOI: 10.1097/00041444-200506000-00004
Source: PubMed

ABSTRACT The higher prevalence of autism in males than in females suggests the possible involvement of the X chromosome. To test the hypothesis that there are mutations increasing susceptibility to autism on the X chromosome, and in particular the distal portion of the long arm that encompasses the FMRI and MECP2 loci, a genetic linkage study was performed. Twenty-two fragile X-negative families multiplex for autism and related disorders were used for the study. Linkage analysis, for markers in the Xq27-q28 region, using model-free likelihood-based analysis, produced a maximum MLOD of 1.7 for the narrowest diagnostic category of the typical autism/severe autism spectrum, and nonparametric analysis produced a maximum non-parametric lod (NPL) score of 2.1 for a broad phenotype diagnostic model. Thus, this study offers modest support for a susceptibility locus for autism within the Xq27-q28 region. Further genetic investigations of this region are warranted.

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