Background. The LRRK2 G2019S mutation is the most common genetic determinant of Parkinson's disease (PD) identified to date. This mutation, reported in both familial and sporadic PD, occurs at elevated frequencies in Maghreb population. In the present study, we examined the prevalence of the G2019S mutation in the Moroccan population and we compared the motor and nonmotor phenotype of G2019S carriers to patients with idiopathic Parkinson's disease. Methods. 100 PD patients were assessed for motor and nonmotor symptoms, current medication, and motor complication including motor fluctuations and dyskinesia. The LRRK2 G2019S mutation was investigated by direct sequencing in patients and ethnically matched controls, all of Moroccan origin. Results. Among the 100 PD Moroccan patients, 41 (41%) were carriers of the G2019S mutation. The mutation frequency was higher among probands with autosomal dominant inheritance (76%) than among sporadic ones (28%). Interestingly, G2019S mutation was also found in 5% of control individuals. Clinically, patients carrying the G2019S mutation have more dystonia (OR = 4.6, p = 0.042) and more sleep disorders (OR = 2.4, p = 0.045) than noncarriers. Conclusions. The LRRK2 G2019S prevalence in Morocco is the highest in the world reported to date. Some clinical features in G2019S carriers such as dystonia and sleep disturbances are worth noting.
Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease. Ten of fifteen causative genes linked to familial forms of PD have been reported to cause autosomal recessive forms. Among them, mutations in the PTEN-induced kinase 1 (PINK1) gene were shown to be responsible for a phenotype characterized by early onset, good response to levodopa, and a benign course. Using chromosomal microarray analysis and Sanger sequencing, we identified a homozygous G/C substitution in a 58-year-old Moroccan man diagnosed with recessive inherited Parkinson's disease. This G-to-C transition occurred at position 1617 leading to an amino acid change L/F at position 539 located in highly conserved motif in the C terminal sequence of PINK1. Interestingly, the c.1617G>C substitution is absent in 192 ethnically matched control chromosomes. Our findings have shown that the p.L539F is a novel mutation located in the C terminal sequence of the PINK1 protein that could be pathogenic and responsible for a clinical phenotype resembling idiopathic Parkinson's disease with rapid progression and early cognitive impairment.
Background: Hypovitaminosis D is reported through the literature to be involved in autoimmune diseases such as multiple sclerosis (MS). In the last decade, numerous studies have investigated the association of single nucleotide polymorphisms (SNPs) with MS, including rs2248359 (CYP24A1) and rs703842 (CYP27B1) that are involved in vitamin D metabolic pathway. However, results were conflicting, probably due to ethnic differences between the studied populations. In this context, the present study aimed to analyze the association between these two SNPs and MS within the Moroccan population. Methods: rs2248359 and rs703842 were genotyped in 113 patients and 146 healthy controls. To assess their association with the disease risk, we compared the genotypic and allelic frequencies between the study groups. We also explored their possible influence on certain clinical features (age at onset, type, disability status and severity score) and with vitamin D3 serum level (DSL) by comparing mean values of these variables between the different genotypes. Results: No statistically significant differences in the distribution of both SNPs were found between patients and controls. A trend has emerged concerning the minor G allele of rs703842 which appears to have a protective effect on developing MS, but this result remained slightly below significance. Also, the two polymorphisms had no impact on the clinical features tested and the DSL. Conclusion: There is no convincing evidence that rs2248359 and rs703842 are associated with MS risk, its clinical features or vitamin D level in MorocHow to cite this paper:
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.