Benign hereditary chorea, not only chorea: a family case presentation

Area of Science:

• Genetics
• Neurology
• Rare Diseases

Background:

• Benign hereditary chorea is a rare, inherited movement disorder.
• Characterized by early-onset, non-progressive chorea, unsteadiness, and often hypothyroidism and lung disease.
• Caused by mutations in the NKX2-1 gene on chromosome 14.

Observation:

• A Norwegian family with eight affected individuals across four generations was studied.
• All affected members exhibited early-onset movement disorders (chorea, motor delay) and learning difficulties.
• Phenotypic variability included chorea, myoclonus, dystonia, ataxia, stuttering, tics, asthma, and hypothyroidism.

Findings:

• Genetic sequencing identified a novel NKX2-1 gene mutation (c.671 T>G, p.Leu224Arg) in all affected family members.
• This mutation is confirmed as the cause of benign hereditary chorea in this Norwegian family.
• The study confirms the wide phenotypic spectrum associated with NKX2-1 mutations.

Implications:

• This research expands the known spectrum of benign hereditary chorea phenotypes.
• It provides crucial genetic information for diagnosis and counseling in affected families.
• Highlights the importance of NKX2-1 gene analysis for movement disorders with associated features.