Gaucher patients with oculomotor abnormalities do not have a unique genotype

Area of Science:

• Neurology
• Genetics
• Ophthalmology

Background:

• Gaucher disease is a lysosomal storage disorder.
• Oculomotor abnormalities, specifically slowed horizontal saccades, are observed in some Gaucher disease patients.
• The relationship between specific genotypes and this clinical presentation is not well-defined.

Purpose of the Study:

• To describe the clinical phenotype of slowed horizontal saccades in non-Ashkenazic American children with Gaucher disease.
• To investigate potential genotype-phenotype correlations for this specific oculomotor abnormality.
• To highlight the implications for clinical management and prediction of disease progression.

Main Methods:

• Descriptive case series of sixteen non-Ashkenazic American children with Gaucher disease.
• Clinical assessment including neuro-ophthalmologic examinations and electroencephalography (EEG).
• Analysis of patient genotypes, focusing on common Gaucher disease mutations.

Main Results:

• All sixteen children presented with slowed horizontal saccades.
• No unique genotype was consistently associated with this oculomotor phenotype; at least five different genotypes were identified among patients with common mutations.
• Patients often exhibited diffusely slowed EEG background but otherwise normal neurological exams.
• These children experienced earlier and more severe systemic manifestations and mortality.

Conclusions:

• Slowed horizontal saccades represent a specific clinical phenotype in Gaucher disease that is not easily predicted by current genotype analysis.
• Careful sequential neuro-ophthalmologic evaluations are crucial for managing Gaucher disease patients.
• Caution is advised when attempting to predict Gaucher disease progression based solely on DNA mutational analysis.