title: High apolipoprotein E4 allele frequency in FXTAS patients.
abstract: OBJECTIVE
  Fragile X-associated tremor/ataxia syndrome is a late-onset neurodegenerative disorder that occurs in FMR1 premutation carriers. It is well known that the apolipoprotein E ε4 allele is a risk factor for neurodegenerative disease. The main goal of this work was to evaluate the apolipoprotein E genotypes and allelic distribution among patients with fragile X-associated tremor/ataxia syndrome.
  
  
  METHODS
  A total of 44 unrelated FMR1 premutation carriers (22 presenting with fragile X-associated tremor/ataxia syndrome and 22 without fragile X-associated tremor/ataxia syndrome) were genotyped.
  
  
  RESULTS
  All the apolipoprotein E ε4/4 genotype carriers detected (100%), and six of the seven apolipoprotein E ε4/3 genotype carriers (85.7%) are patients presenting with fragile X-associated tremor/ataxia syndrome symptoms, whereas only 40% of the apolipoprotein E ε3/3 genotype carriers belong to the fragile X-associated tremor/ataxia syndrome group. The results showed that the presence of the apolipoprotein E ε4 allele increases the risk of developing fragile X-associated tremor/ataxia syndrome (odds ratio = 12.041; P = 0.034).
  
  
  CONCLUSIONS
  On the basis of these results, we conclude that the presence of at least one apolipoprotein E ε4 allele might act as a genetic factor predisposing individuals to develop fragile X-associated tremor/ataxia syndrome.
authors.affiliation: Department of Biochemistry and Molecular Genetics, Hospital Clinic, Barcelona, Spain.
authors.forename: Francisca
authors.initials: F
authors.lastname: Silva
authors.forename: Laia
authors.initials: L
authors.lastname: Rodriguez-Revenga
authors.forename: Irene
authors.initials: I
authors.lastname: Madrigal
authors.forename: Maria Isabel
authors.initials: MI
authors.lastname: Alvarez-Mora
authors.forename: Rafael
authors.initials: R
authors.lastname: Oliva
authors.forename: Montserrat
authors.initials: M
authors.lastname: Milà
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D053318:Apolipoprotein E3 / Q000235:genetics*; D053327:Apolipoprotein E4 / Q000235:genetics*; D001259:Ataxia / Q000235:genetics*; D005260:Female; D051860:Fragile X Messenger Ribonucleoprotein 1 / Q000235:genetics; D005600:Fragile X Syndrome / Q000235:genetics*; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D013030:Spain; D014202:Tremor / Q000235:genetics*; D044465:White People / Q000235:genetics
chemical_list: D053318:Apolipoprotein E3; D053327:Apolipoprotein E4; D051860:Fragile X Messenger Ribonucleoprotein 1; C497683:FMR1 protein, human