Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Mov Disord ; 39(10): 1843-1855, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39051491

RESUMO

BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disease following Alzheimer's disease. Nearly 30 causative genes have been identified for PD and related disorders. However, most of these genes were identified in European-derived families, and little is known about their role in Latin American populations. OBJECTIVES: Our goal was to assess the spectrum and frequency of pathogenic variants in known PD genes in familial PD patients from Latin America. METHODS: We selected 335 PD patients with a family history of PD from the Latin American Research Consortium on the Genetics of PD. We capture-sequenced the coding regions of 26 genes related to neurodegenerative parkinsonism. Of the 335 PD patients, 324 had sufficient sequencing coverage to be analyzed. RESULTS: We identified pathogenic variants in 41 individuals (12.7%) in FBXO7, GCH1, LRRK2, PARK7, PINK1, PLA2G6, PRKN, SNCA, and TARDBP, GBA1 risk variants in 25 individuals (7.7%), and variants of uncertain significance in another 24 individuals (7.4%) in ATP13A2, ATP1A3, DNAJC13, DNAJC6, GBA1, LRKK2, PINK1, VPS13C, and VPS35. Of the 70 unique variants identified, 19 were more frequent in Latin Americans than in any other population. CONCLUSIONS: This is the first screening of known PD genes in a large cohort of patients with familial PD from Latin America. There were substantial differences in the spectrum of variants observed in comparison to previous findings from PD families of European origin. Our data provide further evidence that differences exist between the genetic architecture of PD in Latinos and European-derived populations. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Testes Genéticos , Doença de Parkinson , Humanos , Doença de Parkinson/genética , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Testes Genéticos/métodos , América do Sul , América Central , Predisposição Genética para Doença/genética , Adulto
2.
Mov Disord ; 38(9): 1625-1635, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37469269

RESUMO

BACKGROUND: Sex differences in Parkinson's disease (PD) risk are well-known. However, the role of sex chromosomes in the development and progression of PD is still unclear. OBJECTIVE: The objective of this study was to perform the first X-chromosome-wide association study for PD risk in a Latin American cohort. METHODS: We used data from three admixed cohorts: (1) Latin American Research consortium on the Genetics of Parkinson's Disease (n = 1504) as discover cohort, and (2) Latino cohort from International Parkinson Disease Genomics Consortium (n = 155) and (3) Bambui Aging cohort (n = 1442) as replication cohorts. We also developed an X-chromosome framework specifically designed for admixed populations. RESULTS: We identified eight linkage disequilibrium regions associated with PD. We replicated one of these regions (top variant rs525496; discovery odds ratio [95% confidence interval]: 0.60 [0.478-0.77], P = 3.13 × 10-5 replication odds ratio: 0.60 [0.37-0.98], P = 0.04). rs5525496 is associated with multiple expression quantitative trait loci in brain and non-brain tissues, including RAB9B, H2BFM, TSMB15B, and GLRA4, but colocalization analysis suggests that rs5525496 may not mediate risk by expression of these genes. We also replicated a previous X-chromosome-wide association study finding (rs28602900), showing that this variant is associated with PD in non-European populations. CONCLUSIONS: Our results reinforce the importance of including X-chromosome and diverse populations in genetic studies. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Cromossomos Humanos X , Doença de Parkinson , Feminino , Humanos , Masculino , Estudo de Associação Genômica Ampla , Hispânico ou Latino , América Latina , Doença de Parkinson/genética , Fatores Sexuais , Cromossomos Humanos X/genética , Desequilíbrio de Ligação/genética
3.
Ann Neurol ; 90(3): 353-365, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34227697

RESUMO

OBJECTIVE: This work was undertaken in order to identify Parkinson's disease (PD) risk variants in a Latino cohort, to describe the overlap in the genetic architecture of PD in Latinos compared to European-ancestry subjects, and to increase the diversity in PD genome-wide association (GWAS) data. METHODS: We genotyped and imputed 1,497 PD cases and controls recruited from nine clinical sites across South America. We performed a GWAS using logistic mixed models; variants with a p-value <1 × 10-5 were tested in a replication cohort of 1,234 self-reported Latino PD cases and 439,522 Latino controls from 23andMe, Inc. We also performed an admixture mapping analysis where local ancestry blocks were tested for association with PD status. RESULTS: One locus, SNCA, achieved genome-wide significance (p-value <5 × 10-8 ); rs356182 achieved genome-wide significance in both the discovery and the replication cohorts (discovery, G allele: 1.58 OR, 95% CI 1.35-1.86, p-value 2.48 × 10-8 ; 23andMe, G allele: 1.26 OR, 95% CI 1.16-1.37, p-value 4.55 × 10-8 ). In our admixture mapping analysis, a locus on chromosome 14, containing the gene STXBP6, achieved significance in a joint test of ancestries and in the Native American single-ancestry test (p-value <5 × 10-5 ). A second locus on chromosome 6, containing the gene RPS6KA2, achieved significance in the African single-ancestry test (p-value <5 × 10-5 ). INTERPRETATION: This study demonstrated the importance of the SNCA locus for the etiology of PD in Latinos. By leveraging the demographic history of our cohort via admixture mapping, we identified two potential PD risk loci that merit further study. ANN NEUROL 2021;90:353-365.


Assuntos
Loci Gênicos/genética , Variação Genética/genética , Estudo de Associação Genômica Ampla/métodos , Hispânico ou Latino/genética , Doença de Parkinson/etnologia , Doença de Parkinson/genética , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Polimorfismo de Nucleotídeo Único/genética , América do Sul/etnologia
4.
Mov Disord ; 36(2): 434-441, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33150996

RESUMO

BACKGROUND: Parkinson's disease is the second most common neurodegenerative disorder and affects people from all ethnic backgrounds, yet little is known about the genetics of Parkinson's disease in non-European populations. In addition, the overall identification of copy number variants at a genome-wide level has been understudied in Parkinson's patients. The objective of this study was to understand the genome-wide burden of copy number variants in Latinos and its association with Parkinson's disease. METHODS: We used genome-wide genotyping data from 747 Parkinson's disease patients and 632 controls from the Latin American Research Consortium on the Genetics of Parkinson's disease. RESULTS: Genome-wide copy number burden analysis showed that patients were significantly enriched for copy number variants overlapping known Parkinson's disease genes compared with controls (odds ratio, 3.97; 95%CI, 1.69-10.5; P = 0.018). PRKN showed the strongest copy number burden, with 20 copy number variant carriers. These patients presented an earlier age of disease onset compared with patients with other copy number variants (median age at onset, 31 vs 57 years, respectively; P = 7.46 × 10-7 ). CONCLUSIONS: We found that although overall genome-wide copy number variant burden was not significantly different, Parkinson's disease patients were significantly enriched with copy number variants affecting known Parkinson's disease genes. We also identified that of 250 patients with early-onset disease, 5.6% carried a copy number variant on PRKN in our cohort. Our study is the first to analyze genome-wide copy number variant association in Latino Parkinson's disease patients and provides insights about this complex disease in this understudied population. © 2020 International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , Idade de Início , Variações do Número de Cópias de DNA/genética , Estudo de Associação Genômica Ampla , Hispânico ou Latino/genética , Humanos , América Latina , Pessoa de Meia-Idade , Doença de Parkinson/genética
5.
Cerebellum ; 19(2): 216, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31940124

RESUMO

The original version of this article unfortunately contained some mistakes in Table 2. The additional row (just above SCA2) with the following information "SCA1, 1(1), 1, 50, 74, 24, 46 and 0/1" should be inserted.

6.
Cerebellum ; 19(2): 208-215, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31900855

RESUMO

Relative frequency of hereditary ataxias remains unknown in many regions of Latin America. We described the relative frequency in spinocerebellar ataxias (SCA) due to (CAG)n and to (ATTCT)n expansions, as well as Friedreich ataxia (FRDA), among cases series of ataxic individuals from Peru. Among ataxic index cases from 104 families (38 of them with and 66 without autosomal dominant pattern of inheritance), we identified 22 SCA10, 8 SCA2, 3 SCA6, 2 SCA3, 2 SCA7, 1 SCA1, and 9 FRDA cases (or families). SCA10 was by far the most frequent one. Findings in SCA10 and FRDA families were of note. Affected genitors were not detected in 7 out of 22 SCA10 nuclear families; then overall maximal penetrance of SCA10 was estimated as 85%; in multiplex families, penetrance was 94%. Two out of nine FRDA cases carried only one allele with a GAA expansion. SCA10 was the most frequent hereditary ataxia in Peru. Our data suggested that ATTCT expansions at ATXN10 might not be fully penetrant and/or instability between generations might frequently cross the limits between non-penetrant and penetrant lengths. A unique distribution of inherited ataxias in Peru requires specific screening panels, considering SCA10 as first line of local diagnosis guidelines.


Assuntos
Ataxina-10/genética , Penetrância , Degenerações Espinocerebelares/genética , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peru , Adulto Jovem
7.
Cerebellum ; 18(5): 841-848, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31342269

RESUMO

Spinocerebellar ataxia type 10 (SCA10) is a repeat expansion disease occurring mostly in Latin America, suggesting that the mutation spread with the peopling of the Americas, or that Amerindian populations, have a higher ATXN10 mutability. High frequency of large normal alleles is associated with prevalence and relative frequency of other repeat expansion diseases. To test whether the allele distribution of the SCA10-causing ATXN10 microsatellite in an Amerindian Peruvian population differs from that of other populations. The ATXN10 allele distribution in a Quechua Peruvian population from Puno, Peru, is similar to that of Finland. Mean allele size and mode were also similar to those of Mexico, Japan, and white Europeans. ATXN10 allele distribution in a healthy Amerindian population from Peru does not differ from that of other populations.


Assuntos
Alelos , Ataxina-10/genética , Repetições de Microssatélites/genética , Vigilância da População , Ataxias Espinocerebelares/epidemiologia , Ataxias Espinocerebelares/genética , Expansão das Repetições de DNA/genética , Europa (Continente)/epidemiologia , Humanos , Japão/epidemiologia , México/epidemiologia , Peru/epidemiologia , Vigilância da População/métodos , Ataxias Espinocerebelares/diagnóstico
8.
BMC Health Serv Res ; 19(1): 1017, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31888613

RESUMO

BACKGROUND: Huntington's disease (HD) is a devastating and fatal neurodegenerative disorder that leads to progressive disability, and over time to total dependence. The economic impact of HD on patients living in developing countries like Peru is still unknown. This study aims to estimate the economic burden by estimating direct and indirect costs of Huntington's disease in Peru, as well as the proportion of direct costs borne by patients and their families. METHODS: Disease-cost cross-sectional study where 97 participants and their primary caregivers were interviewed using a common questionnaire. Prevalence and human capital approaches were used to estimate direct and indirect costs, respectively. RESULTS: The average annual cost of HD reached USD 8120 per patient in 2015. Direct non-healthcare costs represented 78.3% of total cost, indirect costs 14.4% and direct healthcare costs the remaining 7.3%. The mean cost of HD increased with the degree of patient dependency: from USD 6572 for Barthel 4 & 5 (slight dependency and total independency, respectively) to USD 23,251 for Barthel 1 (total dependency). Direct costs were primarily financed by patients and their families. CONCLUSIONS: The estimated annual cost of HD for Peruvian society reached USD 1.2 million in 2015. The cost impact of HD on patients and their families is very high, becoming catastrophic for most dependent patients, and thus making it essential to prioritize full coverage by the State.


Assuntos
Efeitos Psicossociais da Doença , Doença de Huntington/economia , Adulto , Estudos Transversais , Feminino , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Peru , Inquéritos e Questionários
9.
Mov Disord Clin Pract ; 10(2): 238-247, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36825038

RESUMO

Background: Juvenile-onset Huntington's Disease (JoHD) or Huntington's disease (HD) with age of onset ≤20 years, is a rare clinical entity that often differs phenotypically from adult HD and represents only 1-15% of total HD cases. Objective: To characterize the genetic and clinical characteristics of 32 JoHD patients seen in a Peruvian Neurogenetics clinic from 2000-2018. Methods: This study is a retrospective clinical and genetic review. The clinical database in Lima, Peru was searched for HD patients seen in clinic between 2000 and 2018. Inclusion criteria were: (1) genetically confirmed disease; and (2) HD age of onset ≤20 years, according to the documented medical history. Results: Among 475 patients with genetically confirmed HD in the database, 32 patients (6.7%) had symptom onset at ≤20 years. Among JoHD patients with a known transmitting parent (30 of 32), paternal transmission accounted for 77% of cases. Anticipation was higher with paternal transmission compared to maternal transmission (27.5 ± 11.5 vs. 11.3 ± 7.1 years). Overall expanded CAG repeat length ranged from 44 to 110, with a mean length of 65.6 ± 15.4, and 14 (44%) cases had repeat length under 60. Of the 32 patients included in the study, 25 had detailed clinical symptomatology available, and many patients had unique clinical features such as prominent sleep disturbance (60% of patients), or parkinsonism (73%). Conclusions: This large case series of JoHD patients characterizes the Peruvian JoHD population, reports on unique familial relationships in JoHD, and highlights the varied symptomatic presentation of this rare disease.

10.
medRxiv ; 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37693616

RESUMO

Background: Parkinson's Disease (PD) has a complex etiology, involving genetic and environmental factors. Most of our current understanding of the disease comes from studies in populations with mostly European ancestry, representing challenges in generalizing findings to other populations with different genetic, social, and environmental contexts. There are scarce studies focused in Latin American populations. The Mexican population is genetically diverse because its admixture from Native American, European, and African ancestries, coupled with the unique environmental conditions, stressing the relevance of establishing genetic studies in this population. Thus, we have established the Mexican Parkinson's Research Network (MEX-PD), a consortium to research the clinical, genetical, environmental, and neurophysiological bases of the phenotypic diversity in Mexican PD patients. Objectives: Describing how MEX-PD was established, the methods and instruments and presenting the first results. Methods: Patients and controls were recruited from medical centers in 20 states of Mexico. Initial recruitment included neurological evaluation, cognitive assessment, and DNA collection. Results: MEX-PD has registered 302 controls and 262 PD patients with a mean age of diagnosis of 61 years (SD=10.86). There were 19.8% PD patients identified with early onset. Levodopa was the most common pharmacological treatment. Conclusions: MEX-PD contributes to understand PD nationally. The information gathered here will allow us to understand the prevalence of mental health, neurological symptoms, and cognitive function in the PD Mexican population and how genetical and environmental factors contributes to those outcomes. These will advocate for personalized treatments and improving quality of life in the Mexican population.

11.
medRxiv ; 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36778409

RESUMO

Sex differences in Parkinson Disease (PD) risk are well-known. However, it is still unclear the role of sex chromosomes in the development and progression of PD. We performed the first X-chromosome Wide Association Study (XWAS) for PD risk in Latin American individuals. We used data from three admixed cohorts: (i) Latin American Research consortium on the GEnetics of Parkinson's Disease (n=1,504) as discover cohort and (ii) Latino cohort from International Parkinson Disease Genomics Consortium (n = 155) and (iii) Bambui Aging cohort (n= 1,442) as replication cohorts. After developing a X-chromosome framework specifically designed for admixed populations, we identified eight linkage disequilibrium regions associated with PD. We fully replicated one of these regions (top variant rs525496; discovery OR [95%CI]: 0.60 [0.478 - 0.77], p = 3.13 × 10 -5 ; replication OR: 0.60 [0.37-0.98], p = 0.04). rs525496 is an expression quantitative trait loci for several genes expressed in brain tissues, including RAB9B, H2BFM, TSMB15B and GLRA4 . We also replicated a previous XWAS finding (rs28602900), showing that this variant is associated with PD in non-European populations. Our results reinforce the importance of including X-chromosome and diverse populations in genetic studies.

12.
Parkinsonism Relat Disord ; 102: 7-15, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35917738

RESUMO

BACKGROUND: Large-scale Parkinson's disease (PD) genome-wide association studies (GWAS) have, until recently, only been conducted on subjects with European-ancestry. Consequently, polygenic risk scores (PRS) constructed using PD GWAS data are likely to be less predictive when applied to non-European cohorts. METHODS: Using GWAS data from the largest study to date, we constructed a PD PRS for a Latino PD cohort (1497 subjects from LARGE-PD) and tested it for association with PD status and age at onset. We validated the PRS performance by testing it in an independent Latino cohort (448 subjects) and by repeating the analysis in LARGE-PD with the addition of 440 external Peruvian controls. We also tested SNCA haplotypes for association with PD risk in LARGE-PD and a European-ancestry PD cohort. RESULTS: The GWAS-significant PD PRS had an area under the receiver-operator curve (AUC) of 0.668 (95% CI: 0.640-0.695) in LARGE-PD. The inclusion of external Peruvian controls mitigated this result, dropping the AUC 0.632 (95% CI: 0.607-0.657). At the SNCA locus, haplotypes differ by ancestry. Ancestry-specific SNCA haplotypes were associated with PD status in both LARGE-PD and the European-ancestry cohort (p-value < 0.05). These haplotypes both include the rs356182 G-allele, but only share 14% of their variants overall. CONCLUSION: The PD PRS has potential for PD risk prediction in Latinos, but variability caused by admixture patterns and bias in a European-ancestry PD PRS data limits its utility. The inclusion of diverse subjects can help elucidate PD risk loci and improve risk prediction in non-European cohorts.


Assuntos
Estudo de Associação Genômica Ampla , Doença de Parkinson , Predisposição Genética para Doença/genética , Haplótipos , Hispânico ou Latino/genética , Humanos , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , alfa-Sinucleína/genética
13.
Genes (Basel) ; 10(8)2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370293

RESUMO

: Hearing loss (HL) is a common sensory disorder affecting over 5% of the global population. The etiology underlying HL includes congenital and acquired causes; genetic factors are the main cause in over 50% of congenital cases. Pathogenic variants in the GJB2 gene are a major cause of congenital non-syndromic hearing loss (NSHL), while their distribution is highly heterogeneous in different populations. To the best of our knowledge, there is no data regarding the genetic etiologies of HL in Peru. In this study, we screened 133 Peruvian families with NSHL living in Lima. We sequenced both exons of the GJB2 gene for all probands. Seven probands with familial NSHL that remained negative for GJB2 variants underwent whole genome sequencing (WGS). We identified biallelic pathogenic variants in GJB2 in 43 probands; seven were heterozygous for only one allele. The c.427C>T variant was the most common pathogenic variant followed by the c.35delG variant. WGS revealed three novel variants in MYO15A in two probands, one of them was predicted to affect splicing and the others produce a premature stop codon. The Peruvian population showed a complex profile for genetic variants in the GJB2 gene, this particular profile might be a consequence of the admixture history in Peru.


Assuntos
Surdez/genética , Polimorfismo de Nucleotídeo Único , Conexina 26 , Conexinas/genética , Humanos , Taxa de Mutação , Miosinas/genética , Linhagem , Peru
14.
Parkinsonism Relat Disord ; 63: 204-208, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30765263

RESUMO

BACKGROUND: Mutations in the glucocerebrosidase (GBA) gene are an important risk factor for Parkinson's disease (PD). However, most GBA genetic studies in PD have been performed in patients of European origin and very few data are available in other populations. METHODS: We sequenced the entire GBA coding region in 602 PD patients and 319 controls from Colombia and Peru enrolled as part of the Latin American Research Consortium on the Genetics of Parkinson's disease (LARGE-PD). RESULTS: We observed a significantly higher proportion of GBA mutation carriers in patients compared to healthy controls (5.5% vs 1.6%; OR = 4.3, p = 0.004). Interestingly, the frequency of mutations in Colombian patients (9.9%) was more than two-fold greater than in Peruvian patients (4.2%) and other European-derived populations reported in the literature (4-5%). This was primarily due to the presence of a population-specific mutation (p.K198E) found only in the Colombian cohort. We also observed that the age at onset was significantly earlier in GBA carriers when compared to non-carriers (47.1 ±â€¯14.2 y vs. 55.9 ±â€¯14.2 y; p = 0.0004). CONCLUSION: These findings suggest that GBA mutations are strongly associated with PD risk and earlier age at onset in Peru and Colombia. The high frequency of GBA carriers among Colombian PD patients (∼10%) makes this population especially well-suited for novel therapeutic approaches that target GBA-related PD.


Assuntos
Glucosilceramidase/genética , Doença de Parkinson/epidemiologia , Doença de Parkinson/genética , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Colômbia/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , Adulto Jovem
16.
Eur J Hum Genet ; 25(3): 332-340, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28000697

RESUMO

Huntington disease (HD) is a dominant neurodegenerative disorder caused by a CAG repeat expansion in the Huntingtin (HTT) gene. HD occurs worldwide, but the causative mutation is found on different HTT haplotypes in distinct ethnic groups. In Latin America, HD is thought to have European origins, but indigenous Amerindian ancestry has not been investigated. Here, we report dense HTT haplotypes in 62 mestizo Peruvian HD families, 17 HD families from across Latin America, and 42 controls of defined Peruvian Amerindian ethnicity to determine the origin of HD in populations of admixed Amerindian and European descent. HD in Peru occurs most frequently on the A1 HTT haplotype (73%), as in Europe, but on an unexpected indigenous variant also found in Amerindian controls. This Amerindian A1 HTT haplotype predominates over the European A1 variant among geographically disparate Latin American controls and in HD families from across Latin America, supporting an indigenous origin of the HD mutation in mestizo American populations. We also show that a proportion of HD mutations in Peru occur on a C1 HTT haplotype of putative Amerindian origin (14%). The majority of HD mutations in Latin America may therefore occur on haplotypes of Amerindian ancestry rather than on haplotypes resulting from European admixture. Despite the distinct ethnic ancestry of Amerindian and European A1 HTT, alleles on the parent A1 HTT haplotype allow for development of identical antisense molecules to selectively silence the HD mutation in the greatest proportion of patients in both Latin American and European populations.


Assuntos
Haplótipos , Proteína Huntingtina/genética , Doença de Huntington/genética , Indígenas Sul-Americanos/genética , Mutação , População Branca/genética , Humanos , Doença de Huntington/etnologia , Linhagem , Peru
17.
NPJ Parkinsons Dis ; 3: 19, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28649619

RESUMO

Mutations in Leucine-Rich Repeat Kinase 2 (LRRK2), primarily located in codons G2019 and R1441, represent the most common genetic cause of Parkinson's disease in European-derived populations. However, little is known about the frequency of these mutations in Latin American populations. In addition, a prior study suggested that a LRRK2 polymorphism (p.Q1111H) specific to Latino and Amerindian populations might be a risk factor for Parkinson's disease, but this finding requires replication. We screened 1734 Parkinson's disease patients and 1097 controls enrolled in the Latin American Research Consortium on the Genetics of Parkinson's disease (LARGE-PD), which includes sites in Argentina, Brazil, Colombia, Ecuador, Peru, and Uruguay. Genotypes were determined by TaqMan assay (p.G2019S and p.Q1111H) or by sequencing of exon 31 (p.R1441C/G/H/S). Admixture proportion was determined using a panel of 29 ancestry informative markers. We identified a total of 29 Parkinson's disease patients (1.7%) who carried p.G2019S and the frequency ranged from 0.2% in Peru to 4.2% in Uruguay. Only two Parkinson's disease patients carried p.R1441G and one patient carried p.R1441C. There was no significant difference in the frequency of p.Q1111H in patients (3.8%) compared to controls (3.1%; OR 1.02, p = 0.873). The frequency of LRRK2-p.G2019S varied greatly between different Latin American countries and was directly correlated with the amount of European ancestry observed. p.R1441G is rare in Latin America despite the large genetic contribution made by settlers from Spain, where the mutation is relatively common.

18.
eNeurologicalSci ; 5: 15-19, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28534048

RESUMO

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL) is a rare, heritable, small vessel vascular disease caused by mutations in the Notch3 gene that is characterized by migraines, subcortical vascular events, cognitive decline, and mood disturbances. However, many CADASIL cases present with unusual symptoms such as status epilepticus, a movement disorder, or sensory dysfunction. This study describes the clinical, genetic, and radiologic characteristics of a Peruvian family with CADASIL in which multiple family members presented with severe olfactory deficits. Seven members of the family have symptoms suggestive of CADASIL, with genetic testing revealing R133C mutations in the two patients who underwent genetic testing. Cognitive testing and olfactory identification testing (Smell Identification Test) were performed in three CADASIL patients revealing total anosmia in two tested patients and severe hyposmia in the other. Olfactory dysfunction has been associated with various neurologic and psychiatric conditions though few studies have linked it with neurovascular disorders such as CADASIL. This first reported case of CADASIL in Peru emphasizes that symptomatic olfactory dysfunction may be an unusual presentation of CADASIL and that olfactory dysfunction is important to evaluate in CADASIL patients.

19.
Rev Peru Med Exp Salud Publica ; 32(4): 787-93, 2015 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-26732930

RESUMO

Neurogenetics is an emerging discipline in Peru that links basic research with clinical practice. The Neurogenetics Research Center located in Lima, Peru is the only unit dedicated to the specialized care of neurogenetic diseases in the country. From the beginning, neurogenetics research has been closely linked to the study of Huntington’s Disease (HD), from the PCR genotyping of the HTT gene, to the current haplogroup studies in HD. Research in other monogenic diseases led to the implementation of alternative methodologies for the genotyping of Fragile X and Myotonic Dystrophy Type 1. Both, national and international collaborative efforts have facilitated the discovery of new genetic variants in complex multigenic diseases such as Parkinson’s disease and Alzheimer’s disease. Additionally, multidisciplinary education and mentoring have allowed for the training of new neurogenetics specialists, supporting the sustained growth of the discipline in the country. The promotion of research in Peru has spurred the growth of neurogenetics research, although limitations in infrastructure, technology, and education remain a challenge for the further growth of research in this field.


Assuntos
Doenças do Sistema Nervoso/genética , Pesquisa Translacional Biomédica , Genótipo , Humanos , Peru
20.
Rev. neuro-psiquiatr. (Impr.) ; 83(4): 278-283, oct-dic 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1180993

RESUMO

SUMMARY Duchenne muscular dystrophy (DMD) is a rapidly progressive dystrophinopathy with X-linked inheritance. This report describes a woman with a family history of male relatives affected by DMD, as she sought out genetic counseling about her concerns related to family planning and risks of eventually having children with the disease. We proposed her to get involved in a pilot program for carrier-status diagnosis and genetic counseling. This case illustrates the importance of a genetic counseling program for diagnosis of asymptomatic carriers in neurogenetic diseases, particularly in regions with low-resource settings. We discussed successes and misunderstandings faced throughout the process, supporting policies for present and future challenges from this and similar kinds of diagnoses.


RESUMEN La distrofia muscular de Duchenne (DMD) es una distrofinopatía rápidamente progresiva con herencia ligada al cromosoma X. Este reporte describe el caso de una mujer con historia familiar de hermano y sobrinos con DMD, que acudió a consulta para orientación e información sobre riesgos inherentes a una eventual planificación familiar. Le propusimos participar en un programa piloto de asesoramiento genético para determinar su estado de portador o no de la variante causal de DMD en la familia. Esta primera experiencia ilustra la importancia de tener un programa de asesoramiento genético para el diagnóstico de portadores asintomáticos de enfermedades neurogenéticas en regiones con bajos recursos. Se incluyen reflexiones y comentarios sobre aspectos positivos y retos presentados durante el proceso, las políticas de apoyo presente y futuro para el afronte de los complejos problemas planteados por éste y similares diagnósticos.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA