We identified a common polymorphism in contactin-associated protein-like 2 (CNTNAP2), a member of the neurexin superfamily, that is significantly associated with autism susceptibility.
We now identified homozygous and compound-heterozygous deletions and mutations via molecular karyotyping and mutational screening in CNTNAP2 and NRXN1 in four patients with severe mental retardation (MR) and variable features, such as autistic behavior, epilepsy, and breathing anomalies, phenotypically overlapping with Pitt-Hopkins syndrome.
Comparison of the clinical and cytogenetic findings of our patients with previously reported patients, supports that haploinsuffiency of CNTNAP2 can result in language delay and/or autism spectrum disorder.
CNTNAP2 is known to be involved in the cause of language and speech disorders and autism spectrum disorder and is in the same pathway as FOXP2, another important language gene, which makes it a candidate gene for causal studies speech and language disorders such as stuttering.
The third interesting SNP rs802568 was at 7q35 within CNTNAP2 (p=8.92 × 10(-4), 1.38 × 10(-5), and 1.62 × 10(-7) for schizophrenia, bipolar disorder and meta-analysis, respectively).
Comparison of the clinical and cytogenetic findings of our patients with previously reported patients, supports that haploinsuffiency of CNTNAP2 can result in language delay and/or autism spectrum disorder.