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Subclinical signs in LRRK2 mutation carriers
Krisztina K Johansen1, Linda R White, Matthew J Farrer
1Department of Neurology, St. Olav's University Hospital, Trondheim, Norway. krisztina.johansen@stolav.no
Parkinsonism & Related Disorders
|June 7, 2011
Summary
Healthy individuals with LRRK2 gene mutations, linked to Parkinson's disease (PD), show early motor and non-motor signs. These subclinical symptoms appear before olfactory loss, offering insights into PD
Area of Science:
- Neurology
- Genetics
Background:
- Parkinson's disease (PD) onset involves debated timing of motor and non-motor symptoms.
- Early PD signs may be detectable in healthy mutation carriers.
- LRRK2 gene mutations are linked to familial PD.
Purpose of the Study:
- To characterize clinically healthy relatives of LRRK2-PD patients.
- To identify early, subclinical signs in LRRK2 mutation carriers.
Main Methods:
- Screened 47 family members for LRRK2 p.G2019S and p.N1437H mutations.
- Conducted neurological exams (UPDRS), olfaction tests, and questionnaires (mood, sleep, cognition).
Main Results:
- 32 participants carried LRRK2 mutations; 15 did not.
- Mutation carriers showed higher UPDRS motor scores, urinary issues, and less sleep.
- Older carriers (≥50) with UPDRS ≥8 had more urinary/constipation problems, higher mood scores, and BMI.
- No significant olfactory decline was observed in either group.
Conclusions:
- Healthy LRRK2 mutation carriers exhibit subclinical motor and non-motor PD signs.
- Olfactory function appears preserved in these early stages.
- Further longitudinal research is needed to correlate these findings with neuroimaging changes.
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