ADHD and Austism May Have Common Gene Variations

Researchers discover that variations in a common gene may contribute to common deficits found in both ADHD and autism.

Genetic linkage of attention-deficit/hyperactivity disorder on chromosome 16p13, in a region implicated in autism.

Attention-deficit/hyperactivity disorder (ADHD) is the most commonly diagnosed behavioral disorder in childhood and likely represents an extreme of normal behavior. ADHD significantly impacts learning in school-age children and leads to impaired functioning throughout the life span. There is strong evidence for a genetic etiology of the disorder, although putative alleles, principally in dopamine-related pathways suggested by candidate-gene studies, have very small effect sizes. We use affected-sib-pair analysis in 203 families to localize the first major susceptibility locus for ADHD to a 12-cM region on chromosome 16p13 (maximum LOD score 4.2; P=.000005), building upon an earlier genomewide scan of this disorder. The region overlaps that highlighted in three genome scans for autism, a disorder in which inattention and hyperactivity are common, and physically maps to a 7-Mb region on 16p13. These findings suggest that variations in a gene on 16p13 may contribute to common deficits found in both ADHD and autism.

Ed. Note:  The research team is comprised of scientists from the Center for Neurobehavioral Genetics and Departments of Psychiatry and Biobehavioral Sciences, Human Genetics, and Biostatistics, University of California, Los Angeles; and Wellcome Trust Centre for Human Genetics, Oxford, United Kingdom.

Source: American Journal of Human Genetics, 2002 Oct;71(4):959-63. Epub 2002 Aug 14.

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