A SWI/SNF-related autism syndrome caused by de novo mutations in ADNP

Abstract

Despite the high heritability of autism spectrum disorders (ASD), characterized by persistent deficits in social communication and interaction and restricted, repetitive patterns of behavior, interests or activities, a genetic diagnosis can be established in only a minority of patients. Known genetic causes include chromosomal aberrations, such as the duplication of the 15q11-13 region, and monogenic causes, as in Rett and fragile-X syndromes. The genetic heterogeneity within ASD is striking, with even the most frequent causes responsible for only 1% of cases at the most. Even with the recent developments in next-generation sequencing, for the large majority of cases no molecular diagnosis can be established. Here, we report ten patients with ASD and other shared clinical characteristics, including intellectual disability and facial dysmorphisms caused by a mutation in ADNP, a transcription factor involved in the SWI/SNF remodeling complex. We estimate this gene to be mutated in at least 0.17% of ASD cases, making it one of the most frequent ASD-associated genes known to date.

Figure 1

Frontal facial photographs of patient 1 (a),2 (b), 4 (c), 5 (d), 6 (e) and 8 (f) at young age. Note the clinical similarities, including a prominent forehead, a thin upper lip and a broad nasal bridge. Consent for the publication of photographs was obtained for these patients (1, 2, 4, 5, 6 and 8).

Figure 2

Schematic overview of the ADNP gene structure and functional domains. Identified mutations and corresponding patients are indicated by black arrows.