title: Genetic aspects of Huntington's disease in Latin America. A systematic review.
abstract: We aimed to present a systematic review on Huntington's disease (HD) in Latin America (LA). PubMed and LILACS were searched up to March 2015, reporting confirmed HD cases in LA. Case series, cross-sectional, case-control, and prospective studies were included. From 534 communications, 47 were eligible. Population-based studies were not found; minimal prevalence of 0.5-4/100,000 was estimated for Venezuela and Mexico. Geographical isolates were well characterized in Venezuela and in Peru. CAG repeats at HTT gene varied between 7-33 and 37-112 in normal and expanded alleles, respectively. Intermediate alleles were found in 4-10% of controls. Ages at onset and the expanded CAG repeats correlated with r from - 0.55 to -0.91. While haplotype patterns of Venezuelan and Brazilian chromosomes were similar to those observed in Europeans, haplotypes from Peruvian HD patients did not match the same pattern. The limited number of papers found suggests that HD is poorly diagnosed in LA. Minimal prevalence seemed to be halfway between those of Caucasians and Asians. Range of CAG repeats was similar to those of Europeans. Haplotype studies indicate that majority of HD patients might be of Caucasian descent; an Asian origin for some Peruvian patients was proposed.
authors.affiliation: Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.|Instituto Nacional de Genética Médica Populacional (INAGEMP), Porto Alegre, Brazil.
authors.forename: R M
authors.initials: RM
authors.lastname: Castilhos
authors.affiliation: Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: M C
authors.initials: MC
authors.lastname: Augustin
authors.affiliation: Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: J A
authors.initials: JA
authors.lastname: Santos
authors.affiliation: Parkinson's Disease and Movement Disorders Program, Hospital de Clínicas, University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: C
authors.initials: C
authors.lastname: Perandones
authors.affiliation: Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.|Departmento de Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.|Serviço de Genética Médica, Hospital de Clinicas de Porto Alegre, Porto Alegre, Brazil.|Laboratório de Identificação Humana, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.
authors.forename: M L
authors.initials: ML
authors.lastname: Saraiva-Pereira
authors.affiliation: Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.|Instituto Nacional de Genética Médica Populacional (INAGEMP), Porto Alegre, Brazil.|Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.|Serviço de Genética Médica, Hospital de Clinicas de Porto Alegre, Porto Alegre, Brazil.|Laboratório de Identificação Humana, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.|Centro de Pesquisa Clínica, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.|Departamento de Medicina Interna, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: L B
authors.initials: LB
authors.lastname: Jardim
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D044466:Asian People / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D006239:Haplotypes; D006801:Humans; D000071058:Huntingtin Protein / Q000235:genetics*; D006816:Huntington Disease / Q000453:epidemiology / Q000208:ethnology / Q000235:genetics*; D007843:Latin America / Q000208:ethnology; D008875:Middle Aged; D015995:Prevalence; D019680:Trinucleotide Repeat Expansion; D044465:White People / Q000235:genetics; D055815:Young Adult
chemical_list: C086055:HTT protein, human; D000071058:Huntingtin Protein
keywords: CAG repeats; HTT gene; Huntington disease; Latin America; genetic epidemiology; polyglutamine diseases