Identification of the Largest SCA36 Pedigree in Asia: with Multimodel Neuroimaging Evaluation for the First Time

Spinocerebellar ataxias (SCAs) are a large group of hereditary neurodegenerative diseases characterized by ataxia and dysarthria. Due to high clinical and genetic heterogeneity, many SCA families are undiagnosed. Herein, using linkage analysis, WES, and RP-PCR, we identified the largest SCA36 pedigree in Asia. This pedigree showed some distinct clinical characteristics. Cognitive impairment and gaze palsy are common and severe in SCA36 patients, especially long-course patients. Although no patients complained of hearing loss, most of them presented with hearing impairment in objective auxiliary examination. Voxel-based morphometry (VBM) demonstrated a reduction of volumes in cerebellum, brainstem, and thalamus (corrected P < 0.05). Reduced volumes in cerebellum were also found in presymptomatic carriers. Resting-state functional MRI (R-fMRI) found reduced ReHo values in left cerebellar posterior lobule (corrected P < 0.05). Diffusion tensor imaging (DTI) demonstrated a reduction of FA values in cerebellum, midbrain, superior and inferior cerebellar peduncle (corrected P < 0.05). MRS found reduced NAA/Cr values in cerebellar vermis and hemisphere (corrected P < 0.05). Our findings could provide new insights into management of SCA36 patients. Detailed auxiliary examination are recommended to assess hearing or peripheral nerve impairment, and we should pay more attention to eye movement and cognitive changes in patients. Furthermore, for the first time, our multimodel neuroimaging evaluation generate a full perspective of brain function and structure in SCA36 patients.