SFARI

Researchers need reliable methods to interpret autism candidate genes, including rodent models to assess the impact of genes on behavior. On 4 February, SFARI hosted a workshop to discuss the role of mouse models and behavioral assays in autism research. The participants concluded that the field should invest in techniques that can be standardized across laboratories and emphasized the importance of mouse models for identifying biomarkers and testing therapies.

Copy number variants (CNVs) are segments of DNA that vary in copy number between different individuals. CNVs confer significant risk of neuropsychiatric disorders, including autism and schizophrenia. Notably, there appears to be a reciprocal relationship between copy number and brain size for certain genetic loci. For example, deletions of the genomic region 16p11.2 tend to be associated with autism and increased head circumference, whereas duplications of the same segment tend to be associated with schizophrenia and smaller head circumference. The contrasting clinical phenotypes that are associated with reciprocal changes in gene dosage could represent opposite extremes of the same neurodevelopmental process.

The unusually high incidence of cranial and facial anomalies among people with autism may provide insight into the underlying biology of the disorder. Curtis Deutsch of the Eunice Kennedy Shriver Center at the University of Massachusetts Medical School and his colleagues are evaluating these anomalies using new, state-of-the-art imaging technology.

The relationship between genetics and autism is not always straightforward, but some autism spectrum disorders are known to be caused by defects in a single gene. These simpler cases give researchers the opportunity to create animal models with the genetic defect and use them to test hypotheses about the mechanisms at work in autism.

Autism arises in early childhood, during a period of intense learning when many of the brain’s connections are modified by experience. Eric Kandel, Yun-Beom Choi and Craig Bailey of Columbia University are using animal models of memory formation to investigate how two autism-associated proteins — neuroligin and neurexin — regulate this process.