Widespread heterogeneous neuronal loss across the cerebral cortex in Huntington's disease.

Huntington's disease is an autosomal dominant neurodegenerative disease characterized by neuronal degeneration in the basal ganglia and cerebral cortex, and a variable symptom profile. Although progressive striatal degeneration is known to occur and is related to symptom profile, little is known about the cellular basis of symptom heterogeneity across the entire cerebral cortex. To investigate this, we have undertaken a double blind study using unbiased stereological cell counting techniques to determine the pattern of cell loss in six representative cortical regions from the frontal, parietal, temporal, and occipital lobes in the brains of 14 Huntington's disease cases and 15 controls.

Cortical interneuron loss and symptom heterogeneity in Huntington disease.

Objective: The cellular basis of variable symptoms in Huntington disease (HD) is unclear. One important possibility is that degeneration of the interneurons in the cerebral cortex, which play a critical role in modulating cortical output to the basal ganglia, might play a significant role in the development of variable symptomatology in HD. This study aimed to examine whether symptom variability in HD is specifically associated with variable degeneration of cortical interneurons.

New Perspectives on the Neuropathology in Huntington's Disease in the Human Brain and its Relation to Symptom Variation.

We review recent investigations regarding the relationship between selective neurodegeneration in the human brain and the variability in symptom profiles in Huntington's disease. Huntington's disease is a genetic neurodegenerative disorder caused by an expanded CAG repeat in exon 1 of the Huntingtin gene on chromosome 4, encoding a protein called huntingtin. The huntingtin protein is expressed ubiquitously in somatic tissue, however, the major pathology affects the brain with profound degeneration in the striatum and the cerebral cortex.

Cell loss in the motor and cingulate cortex correlates with symptomatology in Huntington's disease.

Huntington's disease is an autosomal dominant inherited neurodegenerative disease with motor symptoms that are variably co-expressed with mood and cognitive symptoms, and in which variable neuronal degeneration is also observed in the basal ganglia and the cerebral cortex. We have recently shown that the variable symptomatology in Huntington's disease correlates with the variable compartmental pattern of GABAA receptor and cell loss in the striatum. To determine whether the phenotypic variability in Huntington's disease is also related to variable neuronal degeneration in the cerebral cortex, we undertook a double-blind study using unbiased stereological cell counting methods to determine the pattern of cell loss in the primary motor and anterior cingulate cortices in the brains of 12 cases of Huntington's disease and 15 controls, and collected detailed data on the clinical symptomatology of the patients with Huntington's disease from family members and clinical records.