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Article scientifique
Lettre
Anglais

Mirror extreme BMI phenotypes associated with gene dosage at the chromosome 16p11.2 locus

Contributeurs/tricesJacquemont, Sébastien
Publié dansNature, vol. 478, no. 7367, p. 97-102
Date de publication2011
Résumé

Both obesity and being underweight have been associated with increased mortality. Underweight, defined as a body mass index (BMI) ≤ 18.5 kg per m(2) in adults and ≤ -2 standard deviations from the mean in children, is the main sign of a series of heterogeneous clinical conditions including failure to thrive, feeding and eating disorder and/or anorexia nervosa. In contrast to obesity, few genetic variants underlying these clinical conditions have been reported. We previously showed that hemizygosity of a ∼600-kilobase (kb) region on the short arm of chromosome 16 causes a highly penetrant form of obesity that is often associated with hyperphagia and intellectual disabilities. Here we show that the corresponding reciprocal duplication is associated with being underweight. We identified 138 duplication carriers (including 132 novel cases and 108 unrelated carriers) from individuals clinically referred for developmental or intellectual disabilities (DD/ID) or psychiatric disorders, or recruited from population-based cohorts. These carriers show significantly reduced postnatal weight and BMI. Half of the boys younger than five years are underweight with a probable diagnosis of failure to thrive, whereas adult duplication carriers have an 8.3-fold increased risk of being clinically underweight. We observe a trend towards increased severity in males, as well as a depletion of male carriers among non-medically ascertained cases. These features are associated with an unusually high frequency of selective and restrictive eating behaviours and a significant reduction in head circumference. Each of the observed phenotypes is the converse of one reported in carriers of deletions at this locus. The phenotypes correlate with changes in transcript levels for genes mapping within the duplication but not in flanking regions. The reciprocal impact of these 16p11.2 copy-number variants indicates that severe obesity and being underweight could have mirror aetiologies, possibly through contrasting effects on energy balance.

Mots-clés
  • Adolescent
  • Adult
  • Aged
  • Aging
  • Body Height/genetics
  • Body Mass Index
  • Case-Control Studies
  • Child
  • Child, Preschool
  • Chromosomes, Human, Pair 16/genetics
  • Cohort Studies
  • Comparative Genomic Hybridization
  • Developmental Disabilities/genetics
  • Energy Metabolism/genetics
  • Europe
  • Female
  • Gene Dosage/genetics
  • Gene Duplication/genetics
  • Gene Expression Profiling
  • Genetic Predisposition to Disease/genetics
  • Genome-Wide Association Study
  • Head/anatomy & histology
  • Heterozygote
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Mental Disorders/genetics
  • Middle Aged
  • Mutation/genetics
  • North America
  • Obesity/genetics
  • Phenotype
  • RNA, Messenger/analysis/genetics
  • Sequence Deletion/genetics
  • Thinness/genetics
  • Transcription, Genetic
  • Young Adult
Citation (format ISO)
JACQUEMONT, Sébastien. Mirror extreme BMI phenotypes associated with gene dosage at the chromosome 16p11.2 locus. In: Nature, 2011, vol. 478, n° 7367, p. 97–102. doi: 10.1038/nature10406
Fichiers principaux (1)
Article (Published version)
accessLevelRestricted
Identifiants
ISSN du journal0028-0836
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Informations techniques

Création14/02/2014 18:05:00
Première validation14/02/2014 18:05:00
Heure de mise à jour14/03/2023 21:00:38
Changement de statut14/03/2023 21:00:38
Dernière indexation16/01/2024 09:21:19
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