Deep sequencing reveals 50 novel genes for recessive cognitive disorders

Although many gene defects have been identified for X-linked early-onset cognitive impairment, or intellectual disability, much less is known about genetic determinants of its autosomal recessive forms, which are more common. In a systematic attempt to shed more light on the molecular causes of the condition, homozygosity mapping, exon enrichment and next-generation sequencing were performed in 136 consanguineous families with the condition. Fifty novel candidate genes involved in intellectual disability were identified, as well as new mutations in several genes that had previously been implicated in neurological disorders. Many of the novel candidates interact with known intellectual-disability gene products and are predicted to act in processes that are vital for normal brain development and function.