Evidence map›Paper›PMID 40461735›Full record

SynthesisCerebellum (London, England)2025

Machado-Joseph disease in Brazil and other South American countries: A systematic Review and Meta-analysis of Prevalence, CAG Repeat Lengths, Age At Onset, and Ancestry.

Lucas Schenatto Sena, Leonardo Simão Medeiros, Laura Bannach Jardim

Abstract readSystematic ReviewMeta-Analysis
PubMed Publisher
In one paragraph

Synthesis in Cerebellum (London, England), 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

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4 · The record

Corrections and comments

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5 · Who and what money

Authors and funding

3 authors.

Lucas Schenatto SenaInstituto de Biociências, Universidade de São Paulo, São Paulo, Brazil.
Leonardo Simão MedeirosCentros de Pesquisa Clínica E Experimental, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.
Laura Bannach JardimCentros de Pesquisa Clínica E Experimental, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil. ljardim@hcpa.edu.br.ORCID http://orcid.org/0000-0001-6907-5068

Funding

Hospital de Clínicas de Porto Alegre 2018-0660
6 · The paper itself

Abstract

Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is a CAG expansion (CAGexp) disease whose genetic characteristics in South America (SA) are not well known. Our aim was to perform a systematic review and meta-analysis on the subject. Number of SA cases, ages at onset (AO), normal CAG repeats (CAGnormal) and CAGexp, and haplotypes, were searched in Pubmed, Embase, Lilacs, SciELO, ProQuest™ Dissertations & Theses Citation Index, BDTD and La Referencia by a PROSPERO registered protocol. Quantitative data were meta analysed. 26 non-replicated papers and dissertations out of 713 publications were included. 2,111 SCA3/MJD patients were reported, 16 living in Argentina, 10 in Chile, 41 in Venezuela, 18 in Peru, and 2,026 in Brazil between 2011 and 2024. Four individual-participant data (IPD) were obtained. The mean (95% CI; sample size) of CAGnormal, CAGexp and AO were 21.90 (21.53-22.27; 802) and 74.65 (74.43-74.87; 1,100) repeats, and 34.90 (34.25-35.31; 1,102) years. CAGexp explained 62% of the AO variability in IPD (789). The CAGexp effects over AO varied according to geographical origin, impacting in the models to predict AO. It was similar in three Brazilian cohorts, while among Peruvians the AO seemed to be earlier than expected by their CAGexp legths. Three studies found the rs1048755-rs12895357-rs7158733 haplotypes ACA, CCG and AGA in Brazilian patients. In conclusion, current evidence supports the relationship between SCA3/MJD and Portuguese-Azoreans, while the different CAGexp effects on AO across SA populations need to be studied to determine the underlying modifying factors.

Indexed as

Machado-Joseph DiseaseTrinucleotide Repeat ExpansionAge of OnsetBrazilHumansPrevalenceSouth AmericaAge at onsetCAG repeat lengthGenetic modulatorMachado-Joseph diseasePhenotypic modifierSpinocerebellar ataxia type 3Trait biomarker

Identifiers

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.