title: Genetics of serum BDNF: meta-analysis of the Val66Met and genome-wide association study.
abstract: OBJECTIVE
  Lower levels of serum brain derived neurotrophic factor (BDNF) is one of the best known biomarkers of depression. To identify genetic variants associated with serum BDNF, we tested the Val66Met (rs6265) functional variant and conducted a genome-wide association scan (GWAS).
  
  
  METHODS
  In a community-based sample (N = 2054; aged 19-101, M = 51, SD = 15) from Sardinia, Italy, we measured serum BDNF concentration and conducted a GWAS.
  
  
  RESULTS
  We estimated the heritability of serum BDNF to be 0.48 from sib-pairs. There was no association between serum BDNF and Val66Met in the SardiNIA sample and in a meta-analysis of published studies (k = 13 studies, total n = 4727, P = 0.92). Although no genome-wide significant associations were identified, some evidence of association was found in the BDNF gene (rs11030102, P = 0.001) and at two loci (rs7170215, P = 4.8 × 10⁻⁵ and rs11073742 P = 1.2 × 10⁻⁵) near and within NTRK3 gene, a neurotrophic tyrosine kinase receptor.
  
  
  CONCLUSIONS
  Our study and meta-analysis of the literature indicate that the BDNF Val66Met variant is not associated with serum BDNF, but other variants in the BDNF and NTRK3 genes might regulate the level of serum BDNF.
authors: National Institute on Aging, NIH, DHHS , Baltimore, MD , USA.
authors: Antonio
authors: A
authors: Terracciano
authors: Maria Grazia
authors: MG
authors: Piras
authors: Monia
authors: M
authors: Lobina
authors: Antonella
authors: A
authors: Mulas
authors: Osorio
authors: O
authors: Meirelles
authors: Angelina R
authors: AR
authors: Sutin
authors: Wayne
authors: W
authors: Chan
authors: Serena
authors: S
authors: Sanna
authors: Manuela
authors: M
authors: Uda
authors: Laura
authors: L
authors: Crisponi
authors: David
authors: D
authors: Schlessinger
mesh_terms: D019208:Brain-Derived Neurotrophic Factor / Q000097:blood / Q000235:genetics*; D055106:Genome-Wide Association Study / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007558:Italy / Q000453:epidemiology
chemical_list: D019208:Brain-Derived Neurotrophic Factor