RT Journal Article SR Electronic T1 A 600 kb deletion syndrome at 16p11.2 leads to energy imbalance and neuropsychiatric disorders JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 660 OP 668 DO 10.1136/jmedgenet-2012-101203 VO 49 IS 10 A1 Zufferey, Flore A1 Sherr, Elliott H A1 Beckmann, Noam D A1 Hanson, Ellen A1 Maillard, Anne M A1 Hippolyte, Loyse A1 Macé, Aurélien A1 Ferrari, Carina A1 Kutalik, Zoltán A1 Andrieux, Joris A1 Aylward, Elizabeth A1 Barker, Mandy A1 Bernier, Raphael A1 Bouquillon, Sonia A1 Conus, Philippe A1 Delobel, Bruno A1 Faucett, W Andrew A1 Goin-Kochel, Robin P A1 Grant, Ellen A1 Harewood, Louise A1 Hunter, Jill V A1 Lebon, Sébastien A1 Ledbetter, David H A1 Martin, Christa Lese A1 Männik, Katrin A1 Martinet, Danielle A1 Mukherjee, Pratik A1 Ramocki, Melissa B A1 Spence, Sarah J A1 Steinman, Kyle J A1 Tjernagel, Jennifer A1 Spiro, John E A1 Reymond, Alexandre A1 Beckmann, Jacques S A1 Chung, Wendy K A1 Jacquemont, Sébastien A1 on behalf of the Simons VIP Consortium A1 on behalf of the 16p11.2 European Consortium YR 2012 UL http://jmg.bmj.com/content/49/10/660.abstract AB Background The recurrent ∼600 kb 16p11.2 BP4-BP5 deletion is among the most frequent known genetic aetiologies of autism spectrum disorder (ASD) and related neurodevelopmental disorders. Objective To define the medical, neuropsychological, and behavioural phenotypes in carriers of this deletion. Methods We collected clinical data on 285 deletion carriers and performed detailed evaluations on 72 carriers and 68 intrafamilial non-carrier controls. Results When compared to intrafamilial controls, full scale intelligence quotient (FSIQ) is two standard deviations lower in carriers, and there is no difference between carriers referred for neurodevelopmental disorders and carriers identified through cascade family testing. Verbal IQ (mean 74) is lower than non-verbal IQ (mean 83) and a majority of carriers require speech therapy. Over 80% of individuals exhibit psychiatric disorders including ASD, which is present in 15% of the paediatric carriers. Increase in head circumference (HC) during infancy is similar to the HC and brain growth patterns observed in idiopathic ASD. Obesity, a major comorbidity present in 50% of the carriers by the age of 7 years, does not correlate with FSIQ or any behavioural trait. Seizures are present in 24% of carriers and occur independently of other symptoms. Malformations are infrequently found, confirming only a few of the previously reported associations. Conclusions The 16p11.2 deletion impacts in a quantitative and independent manner FSIQ, behaviour and body mass index, possibly through direct influences on neural circuitry. Although non-specific, these features are clinically significant and reproducible. Lastly, this study demonstrates the necessity of studying large patient cohorts ascertained through multiple methods to characterise the clinical consequences of rare variants involved in common diseases.