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INTRODUCTION: Autosomal recessive cerebellar ataxias (ARCA) are a group of rare and heterogynous neurodegenerative diseases mainly characterized by unbalance and walking difficulty and movement incoordination. OBJECTIVES: To clinically and paraclinically characterize ARCA in the department of Neurology at the Teaching Hospital of Point G and identify the underlying genetic defect. PATIENTS AND METHOD: We have conducted a longitudinal and prospective study from January 2018 to December 2020. Patients with ARCA phenotype seen in the Department of Neurology at the Teaching Hospital of Point “G” were enrolled. RESULTS: We have enrolled 7 families totaling 13 patients after giving an informed verbal and written consent. The sex ratio was 2.2 in favor of males, Kayes region and Fulani ethnic group were respectively the most represented region and ethnic group.Walking difficulty represented the major symptom followed by loss of vibration and joint sense, nystagmus, dysarthria and skeletal deformities. Alpha-foetoprotein level was high in one patient. Genetic testing confirmed Friedreich ataxia in one family and was not conclusive in 4 families. CONCLUSION: This study showed that ARCA are not uncommon in Mali and genetic testing is crucial to confirm the diagnosis.

The neurodegenerative disease Friedreich's ataxia (FRDA) is the most common autosomal-recessively inherited ataxia and is caused by a GAA triplet repeat expansion in the first intron of the frataxin gene. In this disease, transcription of frataxin, a mitochondrial protein involved in iron homeostasis, is impaired, resulting in a significant reduction in mRNA and protein levels. Global gene expression analysis was performed in peripheral blood samples from FRDA patients as compared to controls, which suggested altered expression patterns pertaining to genotoxic stress. We then confirmed the presence of genotoxic DNA damage by using a gene-specific quantitative PCR assay and discovered an increase in both mitochondrial and nuclear DNA damage in the blood of these patients (p

Velocardiofacial syndrome and DiGeorge syndrome have not previously been associated with central nervous system degeneration. We report a 34 year old man who presented for neurological evaluation with cerebellar atrophy of unknown aetiology. On historical review, he had neonatal hypocalcaemia, an atrial septal defect, and a corrected cleft palate. His physical examination showed the characteristic facies of velocardiofacial syndrome as well as dysmetria and dysdiadocho-kinesia consistent with cerebellar degeneration. Molecular cytogenetic studies showed a deletion of 22q11.2. This man is the first reported patient with the association of a neurodegenerative disorder and 22q11.2 deletion syndrome.

An immunohistochemical study was carried out on a twelve-week old fetus, aborted for high risk of Duchenne muscular dystrophy. Southern and FIGE analysis showed an intragenic duplication in the DMD gene, which had previously resulted in a severe Duchenne phenotype in three relatives. Polyclonal antibodies directed against the NH2-terminal half of dystrophin showed a positive reaction an a similar distribution of dystrophin in the skeletal myotubes of a twelve-week old normal fetus and the affected fetus. In contrast, a polyclonal antibody directed against the COOH-terminus of dystrophin, i.e., distal to the mutation in this family, did only react with the myotubes of the normal fetus and not with those of the affected fetus. This indicates the presence of a truncated dystrophin in the affected fetus. Apparently at this stage, before binding of dystrophin to the sarcolemma, no distinction is made yet between normal and abnormal dystrophins. This implies that the potential to bind to the sarcolemma could be a major point of discrimination between normal and defective dystrophins. The truncated dystrophin will probably be degraded in a later stage during fetal development. So it appears that the use of dystrophin immunostaining to confirm high Duchenne risk abortions requires great caution. To prevent false-positive results, the combined use of NH2- and COOH-terminal antibodies is mandatory