Autism spectrum disorders (ASD) form a common group of neurodevelopmental 
disorders appearing to be under polygenic control, but also strongly influenced 
by multiple environmental factors. The brain mechanisms responsible for ASD are 
not understood and animal models paralleling related emotional and cognitive 
impairments may prove helpful in unraveling them. BTBR T+ tf/J (BTBR) mice 
display behaviors consistent with the three diagnostic categories for ASD. They 
show impaired social interaction and communication as well as increased 
repetitive behaviors. This review covers much of the data available to date on 
BTBR behavior, neuroanatomy and physiology in search for candidate biomarkers, 
which could both serve as diagnostic tools and help to design effective 
treatments for the behavioral symptoms of ASD.