title: Clinical features of Parkinson disease patients with homozygous leucine-rich repeat kinase 2 G2019S mutations.
abstract: BACKGROUND
  The G2019S mutation is the most common pathogenic substitution in the leucine-rich repeat kinase 2 (LRRK2) gene, which has recently been identified in familial and sporadic Parkinson disease (PD).
  
  
  OBJECTIVE
  To report the clinical characteristics of PD patients with homozygous LRRK2 6055G>A (G2019S) mutations and to compare them with previously published descriptions of heterozygous patients.
  
  
  METHODS
  Descriptive clinical report from an international consortium of studies. Subjects Patients with familial PD and homozygous LRRK2 mutations included 23 Tunisians, 2 Algerians, 2 US patients, 1 Canadian, and 1 Moroccan.
  
  
  RESULTS
  There were no observable differences between the homozygote and heterozygote phenotypes.
  
  
  CONCLUSIONS
  Parkinson disease related to LRRK2 is characterized by typical clinical features, and the similarities between patients with homozygous and heterozygous mutations do not support a gene dosage effect.
authors.affiliation: Department of Public Health and Primary Care, University of Cambridge, Cambridge, England.
authors.forename: Lianna
authors.initials: L
authors.lastname: Ishihara
authors.forename: Liling
authors.initials: L
authors.lastname: Warren
authors.forename: Rachel
authors.initials: R
authors.lastname: Gibson
authors.forename: Rim
authors.initials: R
authors.lastname: Amouri
authors.forename: Suzanne
authors.initials: S
authors.lastname: Lesage
authors.forename: Alexandra
authors.initials: A
authors.lastname: Dürr
authors.forename: Meriem
authors.initials: M
authors.lastname: Tazir
authors.forename: Zbigniew K
authors.initials: ZK
authors.lastname: Wszolek
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Uitti
authors.forename: William C
authors.initials: WC
authors.lastname: Nichols
authors.forename: Alida
authors.initials: A
authors.lastname: Griffith
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Hattori
authors.forename: David
authors.initials: D
authors.lastname: Leppert
authors.forename: Ray
authors.initials: R
authors.lastname: Watts
authors.forename: Cyrus P
authors.initials: CP
authors.lastname: Zabetian
authors.forename: Tatiana M
authors.initials: TM
authors.lastname: Foroud
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Farrer
authors.forename: Alexis
authors.initials: A
authors.lastname: Brice
authors.forename: Lefkos
authors.initials: L
authors.lastname: Middleton
authors.forename: Faycal
authors.initials: F
authors.lastname: Hentati
mesh_terms: D000368:Aged; D004252:DNA Mutational Analysis / Q000379:methods; D005192:Family Health; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005998:Glycine / Q000235:genetics*; D006801:Humans; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010300:Parkinson Disease / Q000453:epidemiology / Q000235:genetics*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D012694:Serine / Q000235:genetics*
chemical_list: D012694:Serine; C495280:LRRK2 protein, human; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; D017346:Protein Serine-Threonine Kinases; D005998:Glycine