IIRC, I believe this genetic anomaly is one of about ten associated so far with autistic spectrum disorders. From the link in comment# 1:
Replication in an Icelandic Sample
We observed that 3 of 299 subjects with autism spectrum disorder from Iceland carried the 16p11.2 deletion, a finding that was consistent with the 1% frequency observed in children at Children's Hospital Boston who had sporadic developmental delay or autism spectrum disorder (Table 5 of the Supplementary Appendix). One of these deletions was de novo, the origin of the second deletion was not known, and one was inherited from a father who had attention deficit–hyperactivity disorder (ADHD). By contrast, in a control sample of 18,834 subjects who did not undergo screening for a psychiatric or language disorder, only two deletions were observed — in other words, the deletion was observed more often in patients with autism by a factor of 100 (P=3.7x10–5). However, in a study of the same population by investigators at deCODE Genetics, this deletion was observed at a markedly increased rate in subjects with a psychiatric or language disorder. This study showed that the deletion was present in 1 of 648 patients with schizophrenia, 1 of 420 patients with bipolar disorder, 1 of 203 patients with ADHD (the father of a child with autism, as noted above), and 1 of 3000 patients with panic disorder, anxiety, depression, or addiction. In addition, 1 of 748 patients with dyslexia carried the deletion. Overall, in the Icelandic samples, the carrier frequency among patients with autism was 1%; the frequency was approximately 0.1% among patients with a psychiatric or language disorder and 0.01% in the general population.