Elucidation and rescue of amygdala abnormalities in the Fmr1
mutant mouse model of Fragile X Syndrome Children's National
Medical Center Basic & Clinical Although the underlying causes
of autism spectrum disorders (ASD) are complex, two aspects have
emerged from studies over the years: 1) there is a large genetic
component to ASD, and 2) ASD is a disorder of brain development.
Converging lines of evidence support the hypothesis that
mutations in genes that regulate synapse formation and function
underlie ASD. One of the best current models for understanding
the brain abnormalities in ASD is Fragile X Syndrome (FXS). FXS
is a single gene neurodevelopmental disorder that results from
an absence of expression of the mRNA binding protein-encoding
Fmr1 gene. FXS is characterized by cognitive impairment and
impaired social interaction. The latter takes the form of social
avoidance/anxiety and/or autistic behavior, which leads to an
approximately 45% prevalence of DSM-IV diagnosis of ASD in boys
with FXS, thus makin