Clinical, paraclinical and genetic aspects of autosomal recessive cerebellar ataxias (ARCA) in Mali

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.

[Progressive myoclonic epilepsy in the department of neurology of the University Teaching hospital Point "G"]

Background

Progressive Myoclonic Epilepsy (PME) is a heterogeneous group of pathologies associating epileptic seizures and other neurological and non-neurological disorders.

Objectives

We aim to characterize patients with symptoms of PME and identify the underlying genetic disorder.

Methods

After informed consent, the patients seen in the protocol for hereditary neurological diseases and presenting signs of epilepsy without a secondary cause were clinically evaluated over a three-year period in the Department of Neurology of the CHU Point "G". EEG, brain imaging and laboratory tests were performed to consolidate our diagnosis. DNA was extracted for genetic analysis.

Results

141 families including five families with PME totaling eight cases were enrolled. The predominant symptoms in our patients were myoclonus in 87.5% (N = 8), followed by GTCS and cognitive impairment in 50%, each. A notion of parental consanguinity was found in 60% and autosomal recessive transmission evoked in 80% (N = 5). The EEG was pathological in 62.5% and imaging showed ponto-cerebellar atrophy in 25% (N = 8). The combination of sodium valproate and clonazepam was the main treatment. One case of death was recorded.

Conclusion

We report cases of PME in Mali with a possibility of discovering new genes.

[Supporting factors of diarrhoea diseases in the children under 5 years in Commune II of the district of Bamako- Mali]

Diarrhea remains a real public health problem as it is the second leading cause of under-five mortality. In tropical environments, studies show several factors contributing to the frequency and severity of diarrhea. It is in this context that the present study of the factors favoring diarrheal diseases in children from 0 to 5 years old has been carried out.

MATERIALS AND METHODS

Cross-sectional cluster survey involving 200 mothers of 0-5 year-old children from November 2015 to October 2016. The Pearson Chi² test was used with a 95% confidence level.

RESULTS

Married women accounted for 85.5% of our sample, 47% of whom had no education. Of the mothers surveyed, 17% of their children had had at least one episode of diarrhea in the two weeks before the survey. Almost all mothers (94%) washed their hands before feeding their children and 13% did not do so after cleaning the children. Regarding the cleanliness of the concession, it was bad in 23.5%. The majority of mothers (51%) did not know the significance of diarrhea, 43% reported the means of transmission, and 28% had inadequate practice in managing diarrhea. Some factors favor the occurrence of diarrhea such as: mixed breastfeeding that was statistically significant (p = 0.014), as well as poor hand hygiene practices (p = 0.027) and concessions (p = 0.000), as well as than the bad knowledge of the subject (p = 0.000).

CONCLUSION

Our study shows that diarrhea was a disease of the hands rooms, hence the interest of strengthening the awareness of mothers for best practices for behavior change.

Differences in genetic structure assessed using Y-chromosome and mitochondrial DNA markers do not shape the contributions to diversity in African sires

Up to 173 African sires belonging to 11 different subpopulations representative of four cattle groups were analysed for six Y-specific microsatellite loci and a mitochondrial DNA fragment. Differences in Y-chromosome and mtDNA haplotype structuring were assessed. In addition, the effect of such structuring on contributions to total genetic diversity was assessed. Thirty-five Y-chromosome and 71 mtDNA haplotypes were identified. Most Y-chromosomes analysed (73.4%) were of zebu origin (11 haplotypes). Twenty-two Y-haplotypes (44 samples) belonged to the African taurine subfamily Y2a. All mtDNA haplotypes belonged to the "African" taurine T1 haplogroup with 16 samples and nine haplotypes belonging to a recently identified subhaplogroup (T1e). Median-joining networks showed that Y-chromosome phylogenies were highly reticulated with clear separation between zebu and taurine clusters. Mitochondrial haplotypes showed a clear star-like shape with small number of mutations separating haplotypes. Mitochondrial-based F_ST -statistics computed between cattle groups tended to be statistically non-significant (p > .05). Most F_ST values computed among groups and subpopulations using Y-chromosome markers were statistically significant. AMOVA confirmed that divergence between cattle groups was only significant for Y-chromosome markers (Φ_CT  = 0.209). At the mitochondrial level, African sires resembled an undifferentiated population with individuals explaining 94.3% of the total variance. Whatever the markers considered, the highest contributions to total Nei's gene diversity and allelic richness were found in West African cattle. Genetic structuring had no effect on patterns of contributions to diversity.