| Literature DB >> 24764760 |
Lavínia Schuler-Faccini1, Claudio Maria Osorio2, Flavia Romariz3, Milena Paneque4, Jorge Sequeiros4, Laura Bannach Jardim5.
Abstract
Machado-Joseph disease (MJD) is an autosomal dominant, late-onset neurological disorder and the most common form of spinocerebellar ataxia (SCA) worldwide. Diagnostic genetic testing is available to detect the disease-causing mutation by direct sizing of the CAG repeat tract in the ataxin 3 gene. Presymptomatic testing (PST) can be used to identify persons at risk of developing the disease. Genetic counseling provides patients with information about the disease, genetic risks, PST, and the decision-making process. In this study, we present the protocol used in PST for MJD and the relevant observations from two centers: Brazil (Porto Alegre) and Portugal (Porto). We provide a case report that illustrates the significant ethical and psychological issues related to PST in late-onset neurological disorders. In both centers, counseling and PST are performed by a multidisciplinary team, and genetic testing is conducted at the same institutions. From 1999 to 2012, 343 individuals sought PST in Porto Alegre; 263 (77%) of these individuals were from families with MJD. In Porto, 1,530 individuals sought PST between 1996 and 2013, but only 66 (4%) individuals were from families with MJD. In Brazil, approximately 50% of the people seeking PST eventually took the test and received their results, whereas 77% took the test in Portugal. In this case report, we highlight several issues that might be raised by the consultand and how the team can extract significant information. Literature about PST testing for MJD and other SCAs is scarce, and we hope this report will encourage similar studies and enable the implementation of PST protocols in other populations, mainly in Latin America.Entities:
Keywords: Machado-Joseph; SCA3; ataxia; genetic testing; presymptomatic test; psychological issues; psychosocial
Year: 2014 PMID: 24764760 PMCID: PMC3983584 DOI: 10.1590/s1415-47572014000200012
Source DB: PubMed Journal: Genet Mol Biol ISSN: 1415-4757 Impact factor: 1.771
Similarities and differences between the Portuguese and Brazilian programs for genetic counseling and presymptomatic testing.
| Porto (Portugal) | Porto Alegre (Brazil) | ||
|---|---|---|---|
| Team | Clinical geneticist, genetic counselor, psychologist, neurologist, psychiatrist and social worker | Clinical geneticists, genetic counselor, clinical psychologist, neurologist, and psychiatrist | |
| Enrollment criteria | To be at 50% risk, 18 years or older, asymptomatic* (both Programs) | ||
| Pretest | 1st visit | - genetic counseling - psychology evaluation - | - genetic counseling: core staff |
| 2nd visit | 3 weeks after 1st visit: - genetic counseling - social worker’s evaluation - consent form signed | 1 to 2 weeks after 1st visit: - psychological assessment with psychologist or psychiatrist | |
| 3rd visit | 3 weeks after 2nd visit: - communication of results | 1 to 2 weeks after 2nd visit: - new session with psychologist/psychiatrist | |
| 4th visit | No | 1 to 2 weeks after 3rd visit: - 2nd genetic counseling | |
| 5th visit | No | - when results are ready: - communication of results | |
| Neurological evaluation | Always available, but only upon referral of the team (both Programs) | ||
| Psychiatrist? Social worker? | Upon referral of the team Yes | Yes No | |
| Number of blood collections | 2 | 1 | |
| Signed consent form | Yes | No | |
| Disclosure of results | 3rd visit | 5th visit | |
| Post-test follow-ups | 3 weeks and 6 and 12 months after disclosure: psychologist or psychiatrist. 12 months after disclosure: neurologist | 3 weeks and 6 and 12 months after disclosure: psychologist or psychiatrist | |
| Follow-ups upon request | Clinical geneticist, counselor, and/or social worker | Clinical geneticist, counselor, social worker, and/or neurologist | |
For more details and exceptions, see text.