Rare copy number variants cause severe obesity in childhood: recent_highlight

We reported the first evidence that copy number variants are responsible for rare cases of extreme childhood obesity. Copy number variants occur where a segment of DNA is duplicated or deleted and they are already known to cause autism and learning difficulties. One of the most common deletions involved the SH2B1 gene, which encodes an essential component of the leptin signalling pathway. Of particular clinical interest is several children with this deletion had been placed on the "at risk" social services register, based on the assumption that inadequate parenting was the cause of their obesity. Our discovery prompted these decisions to be reconsidered and reversed. Such studies are also contributing to the wider debate concerning the biological and social determinants of obesity. This study is published in Nature