Azorean disease of the nervous system

Area of Science:

• Neurology
• Genetics
• Neuroscience

Background:

• A family of Portuguese ancestry from the Azores presented with a progressive neurologic disease.
• Clinical manifestations included gait ataxia, Parkinsonism-like features, limited eye movements, muscle fasciculations, and loss of lower limb reflexes.

Purpose of the Study:

• To characterize a progressive neurologic disease within a family from the Azores.
• To compare this family's condition with previously reported cases from similar ancestry to identify potential shared genetic etiology.

Main Methods:

• Clinical observation and detailed neurologic examination of affected family members.
• Post-mortem neuropathologic examination of two individuals, including gross and microscopic analysis of brain and spinal cord tissues.

Main Results:

• Neuropathology revealed significant neuronal loss and gliosis in the substantia nigra, pontine nuclei, vestibular nuclei, cranial nerve nuclei, Clarke's columns, and anterior horns.
• Spinal cord findings included fiber loss in fasciculi gracilis and mild pyramidal tract changes.
• Comparison with three previously reported families suggested a potential single genetic entity.

Conclusions:

• The described neurologic disease, characterized by specific clinical and neuropathologic findings, may represent a distinct genetic disorder.
• Variable expression of this genetic entity could explain apparent differences in previously reported families with similar ancestry.