Genetic and Clinical Insights into LRRK2-Associated Parkinson's Disease

Mutations in the LRRK2 gene, which encodes the multidomain enzyme leucine-rich repeat kinase 2, represent one of the most common genetic contributors to Parkinson’s disease worldwide. The G2019S substitution in the kinase domain is the most prevalent variant, exhibiting age-dependent penetrance and a clinical phenotype that overlaps with idiopathic Parkinson’s disease yet often presents with a relatively benign course of non-motor features. Global studies have revealed variable carrier frequencies across populations, with particularly high rates in Ashkenazi Jewish and North African cohorts, reflecting historical founder events. Clinical manifestations in LRRK2-associated cases are dominated by bradykinesia and rigidity, whereas symptoms such as hyposmia, rapid eye movement sleep behaviour disorder and cognitive impairment are less pronounced than in sporadic disease. Emerging data underscore the influence of additional genetic factors, notably polygenic burden, on disease penetrance and age at onset. Longitudinal phenotyping has further delineated prodromal signs and highlighted the need for genotype-specific criteria to capture early disease evolution. At a molecular level, pathogenic LRRK2 variants perturb kinase activity and cellular homeostasis, affecting vesicular trafficking, mitochondrial integrity and inflammatory pathways. These mechanistic insights have spurred development of LRRK2-targeted inhibitors and informed stratification strategies for clinical trials. Collectively, genetic and clinical research into LRRK2-associated Parkinson’s disease illuminates the interplay between inherited susceptibility, environmental modifiers and neurodegenerative processes, offering a paradigm for precision medicine in movement disorders.

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Genetic and Clinical Insights into LRRK2-Associated Parkinson's Disease publication trend

The graph below shows the total number of articles in genetic and clinical insights into lrrk2-associated parkinson's disease across all publications each year (not limited to Nature Index journals).

Technical terms

Penetrance: The proportion of individuals carrying a pathogenic variant who develop clinical symptoms by a given age.

Polygenic risk score: A composite metric summarising the cumulative effect of multiple common genetic variants on disease susceptibility.

Phenoconversion: The transition from an asymptomatic genetic carrier state to manifest clinical disease.

Prodromal phase: The early, often subclinical period during which subtle signs of disease emerge prior to overt diagnosis.

Brain-age gap: The difference between an individual’s estimated brain age, derived from imaging data, and their actual chronological age, reflecting deviations in brain integrity.

References

1. Genetic analysis and natural history of Parkinson’s disease due to the LRRK2 G2019S variant. Brain (2024).
2. Who is at Risk of Parkinson Disease? Refining the Preclinical Phase of GBA1 and LRRK2 Variant Carriers: a Clinical, Biochemical, and Imaging Approach. Current Neurology and Neuroscience Reports (2023).
3. Brain age in genetic and idiopathic Parkinson's disease. Brain Communications (2024).
4. Phenotype, genotype, and worldwide genetic penetrance of LRRK2-associated Parkinson's disease: a case-control study. The Lancet Neurology (2008).
5. Nonmotor Symptoms in LRRK2 G2019S Associated Parkinson’s Disease. PLOS ONE (2014).