title: Decision trees for the analysis of genes involved in Alzheimer's disease pathology.
abstract: BACKGROUND
  Alzheimer's disease (AD) is characterized by a gradual loss of memory, orientation, judgement and language. There is still no cure for this disorder. AD pathogenesis remains fairly unknown and its underlying molecular mechanisms are not yet fully understood. Several studies have shown that the abnormal accumulation of beta-amyloid and tau proteins occurs 10 to 20 years before the onset of symptoms of the disease, so it is extremely important to identify changes in the brain before the first symptoms.
  
  
  METHODS
  We used decision trees to classify 31 individuals (9 healthy controls and 22 AD patients in three different stages of disease) according to the expression of 69 genes previously reported in a meta-analysis, plus the expression levels of APP, APOE, BACE1, NCSTN, PSEN1, PSEN2 and MAPT. We also included in our analysis the MMSE (Mini-Mental State Examination) scores and number of NFT (neurofibrillary tangles).
  
  
  RESULTS
  Results allowed us to generate a model of classification values for different AD stages of severity, according to MMSE scores, and achieve the identification of the expression level of protein tau that may possibly determine the onset (incipient stage) of AD.
  
  
  CONCLUSIONS
  We used decision trees to model the different stages of AD (severe, moderate, incipient and control) based on the meta-analysis of gene expression levels plus MMSE and NFT scores. Both classifiers reported the variable MMSE as most informative, however it we were found that the protein tau also an important role in the onset of AD.
authors.affiliation: Doctorado en Investigaciones Cerebrales, Universidad Veracruzana, Av. Luis Castelazo Ayala S/N, Xalapa, Veracruz 91190, Mexico.
authors.forename: Sonia L
authors.initials: SL
authors.lastname: Mestizo Gutiérrez
authors.affiliation: Doctorado en Ciencias Biomédicas, Universidad Veracruzana, Av. Luis Castelazo Ayala S/N, Xalapa, Veracruz, Mexico.
authors.forename: Marisol
authors.initials: M
authors.lastname: Herrera Rivero
authors.affiliation: Departamento de Inteligencia Artificial, Universidad Veracruzana, Sebastián Camacho 5, Centro, Xalapa, Veracruz 91000, Mexico.
authors.forename: Nicandro
authors.initials: N
authors.lastname: Cruz Ramírez
authors.affiliation: Centro de Investigaciones Cerebrales, Cuerpo Académico de Neuroquímica, Universidad Veracruzana, Av. Luis Castelazo Ayala S/N, Xalapa, Veracruz, Mexico.
authors.forename: Elena
authors.initials: E
authors.lastname: Hernández
authors.affiliation: Centro de Investigaciones Cerebrales, Cuerpo Académico de Neuroquímica, Universidad Veracruzana, Av. Luis Castelazo Ayala S/N, Xalapa, Veracruz, Mexico. Electronic address: garanda@uv.mx.
authors.forename: Gonzalo E
authors.initials: GE
authors.lastname: Aranda-Abreu
mesh_terms: D000544:Alzheimer Disease / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D016229:Amyloid beta-Peptides / Q000096:biosynthesis; D005786:Gene Expression Regulation; D006801:Humans; D008954:Models, Biological; D016875:tau Proteins / Q000096:biosynthesis
chemical_list: D016229:Amyloid beta-Peptides; C054369:MAPT protein, human; D016875:tau Proteins
keywords: Gene expression; MAPT; MMSE; Microarray