Glitches in Gene Linked to Autism
Japanese Study Shows Unusual DNA Patterns on Gene in Autistic Patients
March 22, 2007 -- Japanese researchers report that glitches in a gene they
studied -- called the CADPS2 gene -- may be associated with autism.
Several other genes have been linked to autism. However, the disorder's
exact cause and its full genetic profile are not yet established.
Last week, an American gene expert told WebMD that 100 or more genes may
affect autism risk.
The Japanese scientists in this study included Teiichi Furuichi, PhD, of the
Laboratory for Molecular Neurogenesis at the RIKEN Brain Science Institute in
They studied the CADPS2 gene in mice as well as in people.
In lab tests, the researchers deleted part of the CADPS2 gene in mice. For
comparison, they left the gene intact in other mice.
The mice with the disrupted CADPS2 gene became less social and less
interested in exploring a new environment than mice with an intact CADPS2
Those with the disrupted CADPS2 gene also became hyperactive and started
having disruptions in their sleep patterns. However, their vision, hearing,
smell, and motor skills were similar to mice with an intact gene.
The behavioral changes in the mice with the disrupted CADPS2 gene are
similar to several autism symptoms, the researchers point out.
Furuichi and colleagues also screened the genes of 252 autistic
patients. They found seven unusual arrangements of DNA within the CADPS2
gene in these patients.
The DNA patterns seen haven't been reported in healthy people without
autism, note Furuichi and colleagues.
Lastly, the researchers screened the CADPS2 gene in 218 people with bipolar
disorder. None of the unusual DNA arrangements seen in the autism patients
appeared in the bipolar patients.
However, Furuichi's team stresses that their human DNA studies don't prove
that those particular CADPS2 variations cause autism.