For more than 12 years, scientists have noticed that some individuals with autism also have dup15q. In fact, idic(15) is the most frequently identified chromosome problem in individuals with autism. (A chromosome anomaly involves extra or missing chromosomal material, not changes within the genes such as Fragile X syndrome). It is suggested that the co-occurrence of autism and idic(15) is not by chance. There may be a gene or genes in the 15q11.2-q13.1 region that is/are related to the development of autism in some individuals.
Genetic research studies of individuals without chromosome anomalies also support this idea that an autism-related gene may be present in 15q11.2-q13.1. Specifically, research studies found that certain DNA markers from the 15q11.2-q13.1 region were found more often in individuals with autism than in individuals without autism. Although these DNA markers are too small to be genes, they suggest that researchers may be getting close to finding an autism gene in this region.