A genomic map for rare copy number variants (CNVs) in intellectual disability and developmental delay is reported this week in Nature Genetics. The work provides a genome-wide morbidity map for CNVs that will be important for clinical and research studies.
Evan Eichler and colleagues examined CNVs in 15,767 children with various developmental and intellectual disabilities. They found an excess of large CNVs in these pediatric cases compared to adult controls, with the disease risk increasing with CNV size. They also found that the large CNV burden was higher among individuals with more severe developmental disorders. They suggest that 14.2% of developmental delay in these children may be explained by large CNVs. They also identify 59 potentially pathogenic CNVs and highlight genes that may play a role in these disorders.