title: Alcohol dehydrogenase 2 genotype and allelic variants are not associated with the risk for essential tremor.
abstract: OBJECTIVE
  To investigate the possible association between alcohol dehydrogenase 1B, beta-polypeptide (ADH2) genotype and allelic variants and the risk for developing essential tremor (ET).
  
  
  METHODS
  Leukocytary DNA from 204 ET patients and 200 healthy controls was studied for the genotype ADH2 and the occurrence of ADH2 allelic variants using allele-specific polymerase chain reaction amplification and MslI-restriction fragment length polymorphism's analyses.
  
  
  RESULTS
  The frequencies of the ADH2*1/ADH2*2 genotype and of the allelic variant ADH2*2 did not differ significantly in ET patients when compared with those of the controls. The mean age at onset of ET did not differ significantly between patients with genotypes ADH2*1/ADH2*2 and ADH2*1/ADH2*1. The frequencies of the genotype ADH2*1/ADH2*2 and of the allelic variant ADH2*2 in patients with voice, tongue, and chin tremors did not differ from those of the controls, whereas patients with voice tremor showed lower frequencies of mutated genotypes and ADH2*2 alleles. The frequencies of ADH2 genotypes and ADH2 alleles did not differ significantly between patients who did not drink ethanol and those who reported improvement, no improvement, or unknown response of tremor to ethanol.
  
  
  CONCLUSIONS
  These results suggest that ADH2 genotype and allelic variants are not associated with the risk for ET in white Spanish people.
authors.affiliation: Department of Pharmacology and Psychiatry, Medical School, University of Extremadura, Badajoz, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Martínez
authors.forename: Elena
authors.initials: E
authors.lastname: García-Martín
authors.forename: Hortensia
authors.initials: H
authors.lastname: Alonso-Navarro
authors.forename: Julián
authors.initials: J
authors.lastname: Benito-León
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Puertas
authors.forename: Lluisa
authors.initials: L
authors.lastname: Rubio
authors.forename: Tomás
authors.initials: T
authors.lastname: López-Alburquerque
authors.forename: José Augusto G
authors.initials: JA
authors.lastname: Agúndez
authors.forename: Félix Javier
authors.initials: FJ
authors.lastname: Jiménez-Jiménez
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000426:Alcohol Dehydrogenase / Q000235:genetics*; D016022:Case-Control Studies; D004252:DNA Mutational Analysis; D020329:Essential Tremor / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012306:Risk
chemical_list: C489332:ADH1B protein, human; D000426:Alcohol Dehydrogenase