Author Correction: A framework to identify contributing genes in patients with Phelan-McDermid syndrome

Phelan-McDermid syndrome (PMS) is characterized by a variety of clinical symptoms with heterogeneous degrees of severity, including intellectual disability (ID), absent or delayed speech, and autism spectrum disorders (ASD). It results from a deletion of the distal part of chromosome 22q13 that in most cases includes the SHANK3 gene. SHANK3 is considered a major gene for PMS, but the factors that modulate the severity of the syndrome remain largely unknown. In this study, we investigated 85 patients with different 22q13 rearrangements (78 deletions and 7 duplications). We first explored the clinical features associated with PMS, and provide evidence for frequent corpus callosum abnormalities in 28% of 35 patients with brain imaging data. We then mapped several candidate genomic regions at the 22q13 region associated with high risk of clinical features, and suggest a second locus at 22q13 associated with absence of speech. Finally, in some cases, we identified additional clinically relevant copy-number variants (CNVs) at loci associated with ASD, such as 16p11.2 and 15q11q13, which could modulate the severity of the syndrome. We also report an inherited SHANK3 deletion transmitted to five affected daughters by a mother without ID nor ASD, suggesting that some individuals could compensate for such mutations. In summary, we shed light on the genotype-phenotype relationship of patients with PMS, a step towards the identification of compensatory mechanisms for a better prognosis and possibly treatments of patients with neurodevelopmental disorders.
The underlying genetics of Phelan-McDermid syndrome Multiple chromosomal changes may impact the severity of symptoms in people with Phelan-McDermid syndrome (PMS). Thomas Bourgeron of the Institut Pasteur and colleagues in France conducted genomic analyses and explored the clinical features of 85 people with PMS, a condition caused by a deletion in the long arm of chromosome 22. It is often associated with severe symptoms such as intellectual disability, autism, and seizures. The chromosomal changes in 65% of those studied were not inherited. MRI brain scans showed visible abnormalities in 23 of 35 patients imaged. The size of the chromosomal deletion varied. Patients with small deletions were more likely to have autistic symptoms while those with large deletions were more likely to be unable to talk. The team also identified genes in chromosome 22 and in other regions of the genome that could modify the severity of PMS symptoms.