Non-motor signs and symptoms are known to often impair quality of life and function more than chorea in Huntington’s disease. Among those has been the intriguing observation of olfactory deficits, which may occur quite early in the course of the disease. Several hypotheses had been formulated to explain this disturbance, including cognitive impairment such as odor memory, identification and quality discrimination, but the idea of a more distal deficit was controversially debated. In this study the authors nicely describe the presence of typical aggregates containing huntingtin in the olfactory bulb, confirming its involvement in olfactory deficits. It will be very interesting to further explore the relationship between morphological findings and functional olfactory assessment over different stages of the disease. These findings provide a further example of similarities in pathogenetic mechanisms underlying neurodegenerative disorders. New studies in Parkinson’s disease examine the usefulness of nasal tissue assessment. The perspective to explore this in Huntington’s disease is quite exciting.
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