[Mouse model for human chromosome abnormality].

Autism is a complex psychiatric illness which has received considerable attention as a developmental brain disorder. Substantial evidence suggests that chromosomal abnormalities contribute to autism risk. The duplication of human chromosome 15q11-13 is known to be the most frequent cytogenetic abnormality in autism. We have modeled this genetic change in mice using chromosome engineering to generate a 6.3-Mb duplication of the conserved linkage group on mouse chromosome 7. Mice with a paternal duplication display autistic behavioral features such as poor social interaction and stereotypical behavior, and exhibit abnormal ultrasonic vocalizations. This chromosome-engineered mouse model for autism seems to replicate various aspects of human autistic phenotypes and validates the relevance of the human chromosome abnormality. This model will be a founder mouse for forward genetics of autistic disease and an invaluable tool for its therapeutic development. I will present our analyses on these mice towards understanding the molecular pathophysiology of autism spectrum disorders.