title: Copy number variation of the APC gene is associated with regulation of bone mineral density.
abstract: BACKGROUND
  Genetic studies of osteoporosis have commonly examined SNPs in candidate genes or whole genome analyses, but insertions and deletions of DNA, collectively called copy number variations (CNVs), also comprise a large amount of the genetic variability between individuals. Previously, SNPs in the APC gene have been strongly associated with femoral neck and lumbar spine volumetric bone mineral density in older men. In addition, familial adenomatous polyposis patients carrying heterozygous mutations in the APC gene have been shown to have significantly higher mean bone mineral density than age- and sex-matched controls suggesting the importance of this gene in regulating bone mineral density. We examined CNV within the APC gene region to test for association with bone mineral density.
  
  
  METHODS
  DNA was extracted from venous blood, genotyped using the Human Hap610 arrays and CNV determined from the fluorescence intensity data in 2070 Caucasian men and women aged 47.0 ± 13.0 (mean ± SD) years, to assess the effects of the CNV on bone mineral density at the forearm, spine and total hip sites.
  
  
  RESULTS
  Data for covariate adjusted bone mineral density from subjects grouped by APC CNV genotype showed significant difference (P=0.02-0.002). Subjects with a single copy loss of APC had a 7.95%, 13.10% and 13.36% increase in bone mineral density at the forearm, spine and total hip sites respectively, compared to subjects with two copies of the APC gene.
  
  
  CONCLUSIONS
  These data support previous findings of APC regulating bone mineral density and demonstrate that a novel CNV of the APC gene is significantly associated with bone mineral density in Caucasian men and women.
authors.affiliation: Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands 6009, Australia. Shelby.Chew@health.wa.gov.au
authors.forename: Shelby
authors.initials: S
authors.lastname: Chew
authors.forename: Zari
authors.initials: Z
authors.lastname: Dastani
authors.forename: Suzanne J
authors.initials: SJ
authors.lastname: Brown
authors.forename: Joshua R
authors.initials: JR
authors.lastname: Lewis
authors.forename: Frank
authors.initials: F
authors.lastname: Dudbridge
authors.forename: Nicole
authors.initials: N
authors.lastname: Soranzo
authors.forename: Gabriela L
authors.initials: GL
authors.lastname: Surdulescu
authors.forename: J Brent
authors.initials: JB
authors.lastname: Richards
authors.forename: Tim D
authors.initials: TD
authors.lastname: Spector
authors.forename: Scott G
authors.initials: SG
authors.lastname: Wilson
mesh_terms: D025601:Adenomatous Polyposis Coli Protein / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density / Q000235:genetics*; D056915:DNA Copy Number Variations / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000235:genetics; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D055815:Young Adult
chemical_list: D025601:Adenomatous Polyposis Coli Protein