title: RT-qPCR study on post-mortem brain samples from patients with major psychiatric disorders: reference genes and specimen characteristics.
abstract: BACKGROUND
  Gene expression studies conducted in post-mortem human brain samples have the potential to identify relevant genes implicated in psychiatric disorders. Although reverse transcription quantitative real-time PCR (RT-qPCR) has emerged as the method of choice for specific gene expression studies, it requires the use of stable reference genes, and it is necessary to control for pre- and post-mortem factors to obtain reliable data.
  
  
  OBJECTIVE
  The aim of this study was to identify suitable reference genes and specimen characteristics that can be taken into account when comparing mRNA expression data between post-mortem brain specimens from psychiatric patients and controls.
  
  
  METHODS
  We used a selection of suitably matched occipital cortex specimens from subjects in each of the following groups: schizophrenia (N = 15), bipolar disorder (N = 13), major depressive disorder (N = 15), and control (N = 15). Quantitative and qualitative RNA analyses were performed prior to RT-qPCR and gene expression stability was evaluated with geNorm and NormFinder.
  
  
  RESULTS
  We identified GAPDH, RPS17, RPL30, RPLP0, and TFRC as potential reference genes from a sample plate containing 32 candidates commonly used as reference genes. Further analyses of these 5 genes highlighted that 1) they are suitable reference genes for RT-qPCR studies in these post-mortem brain samples from psychiatric patients, and 2) the RNA quality index is highly correlated with gene expression values (r = -0.681, p < 0.0001).
  
  
  CONCLUSIONS
  In addition to controlling for pre- and post-mortem factors and selecting stable reference genes for normalization, sample sets should be matched with regard to RNA quality.
authors.affiliation: Hospital Universitari Psiquiàtric Institut Pere Mata, IISPV. Universitat Rovira i Virgili, C/ Sant Llorenç 21, 43201 Reus, Spain.
authors.forename: Nerea
authors.initials: N
authors.lastname: Abasolo
authors.forename: Helena
authors.initials: H
authors.lastname: Torrell
authors.forename: Bàrbara
authors.initials: B
authors.lastname: Roig
authors.forename: Sílvia
authors.initials: S
authors.lastname: Moyano
authors.forename: Elisabet
authors.initials: E
authors.lastname: Vilella
authors.forename: Lourdes
authors.initials: L
authors.lastname: Martorell
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism; D000328:Adult; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D001344:Autopsy / Q000379:methods; D001714:Bipolar Disorder / Q000378:metabolism; D003865:Major Depressive Disorder / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D009778:Occipital Lobe / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D011990:Receptors, Transferrin / Q000235:genetics / Q000378:metabolism; D012015:Reference Standards; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012269:Ribosomal Proteins / Q000235:genetics / Q000378:metabolism; D012559:Schizophrenia / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D015703:Antigens, CD; C068126:CD71 antigen; C409587:GRAP2 protein, human; D012333:RNA, Messenger; D011990:Receptors, Transferrin; D012269:Ribosomal Proteins