title: Low AMY1 Gene Copy Number Is Associated with Increased Body Mass Index in Prepubertal Boys.
abstract: Genome-wide association studies have identified more than 60 single nucleotide polymorphisms associated with Body Mass Index (BMI). Additional genetic variants, such as copy number variations (CNV), have also been investigated in relation to BMI. Recently, the highly polymorphic CNV in the salivary amylase (AMY1) gene, encoding an enzyme implicated in the first step of starch digestion, has been associated with obesity in adults and children. We assessed the potential association between AMY1 copy number and a wide range of BMI in a population of Italian school-children.
  
  
  
  744 children (354 boys, 390 girls, mean age (±SD): 8.4±1.4years) underwent anthropometric assessments (height, weight) and collection of saliva samples for DNA extraction. AMY1 copies were evaluated by quantitative PCR.
  
  
  
  A significant increase of BMI z-score by decreasing AMY1 copy number was observed in boys (β: -0.117, p = 0.033), but not in girls. Similarly, waist circumference (β: -0.155, p = 0.003, adjusted for age) was negatively influenced by AMY1 copy number in boys. Boys with 8 or more AMY1 copy numbers presented a significant lower BMI z-score (p = 0.04) and waist circumference (p = 0.01) when compared to boys with less than 8 copy numbers.
  
  
  
  In this pediatric-only, population-based study, a lower AMY1 copy number emerged to be associated with increased BMI in boys. These data confirm previous findings from adult studies and support a potential role of a higher copy number of the salivary AMY1 gene in protecting from excess weight gain.
authors.affiliation: Department of Paediatrics, University of Chieti, Chieti, Italy.|Clinical Research Centre, Centre of Excellence on Aging, University of Chieti, Chieti, Italy.
authors.forename: M Loredana
authors.initials: ML
authors.lastname: Marcovecchio
authors.affiliation: Department of Pharmacy, University of Chieti, Chieti, Italy.
authors.forename: Rosalba
authors.initials: R
authors.lastname: Florio
authors.affiliation: Department of Pharmacy, University of Chieti, Chieti, Italy.|Clinical Research Centre, Centre of Excellence on Aging, University of Chieti, Chieti, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Verginelli
authors.affiliation: Department of Pharmacy, University of Chieti, Chieti, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: De Lellis
authors.affiliation: Department of Zoology, University of Oxford, Oxford, United Kingdom.
authors.forename: Cristian
authors.initials: C
authors.lastname: Capelli
authors.affiliation: Department of Pharmacy, University of Chieti, Chieti, Italy.
authors.forename: Delfina
authors.initials: D
authors.lastname: Verzilli
authors.affiliation: Department of Paediatrics, University of Chieti, Chieti, Italy.|Clinical Research Centre, Centre of Excellence on Aging, University of Chieti, Chieti, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Chiarelli
authors.affiliation: Department of Paediatrics, University of Chieti, Chieti, Italy.|Clinical Research Centre, Centre of Excellence on Aging, University of Chieti, Chieti, Italy.
authors.forename: Angelika
authors.initials: A
authors.lastname: Mohn
authors.affiliation: Department of Pharmacy, University of Chieti, Chieti, Italy.|Clinical Research Centre, Centre of Excellence on Aging, University of Chieti, Chieti, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Cama
mesh_terms: D015992:Body Mass Index; D002648:Child; D056915:DNA Copy Number Variations / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D004063:Digestion / Q000235:genetics; D005260:Female; D018628:Gene Dosage / Q000235:genetics*; D055106:Genome-Wide Association Study / Q000379:methods; D006801:Humans; D008297:Male; D009765:Obesity / Q000235:genetics; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D012463:Saliva / Q000378:metabolism; D013213:Starch / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics*; D055105:Waist Circumference / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; C116115:MYCBP protein, human; D014157:Transcription Factors; D013213:Starch