In this study, Dr. Lewis and colleagues will develop a mouse model of restricted, repetitive behaviors (RRBs) which will allow them to identify variations in the mouse genome associated with these behaviors. These researchers have previously identified an inbred mouse line that displays both repetitive behaviors (jumping, flipping, and weaving) and restricted behaviors (reduced exploration of the environment). The present research will examine the genetic basis of these behaviors, characterizing the regions of genomic DNA which are associated with these behaviors. This may lead to the identification of gene variants which are involved in the development of RRBs. The examination of genetic variation in a mouse model of RRB should have direct value for clinical genetic studies of ASDs, and aid in understanding the underlying biology of this diagnostic feature of autism.