Mucopolysaccharidoses types I and IIIA: Diagnosis and identification of novel polymorphisms associated with common mutations in Moroccan patients.

Background: Mucopolysaccharidoses types I and IIIA are lysosomal storage diseases caused by mutations in the Purpose: The study targeted and investigated the p.Pro533Arg mutation, known to cause mucopolysaccharidosis type I, and the p.Arg377Cys mutation, associated with mucopolysaccharidosis IIIA, in newly recruited Moroccan families. In parallel, variants/polymorphisms associated with these mutations were searched for. Methods: Researchers employed RFLP assays for the p.Pro533Arg and p.Arg377Cys mutations and genomic PCR sequencing for variant detection. PolyPhen-2, MutPred2, SIFT, and MutationTaster were used to assess the pathogenicity of these variants, helping to evaluate their potential impact on disease. Results: The p.Pro533Arg mutation was found in newly recruited families with Hurler syndrome, consistent with previous findings. Similarly, the p.Arg377Cys mutation was present in a newly recruited family with Sanfilippo A syndrome. DNA sequencing revealed five SNPs four in the Conclusion: The p.Pro533Arg and p.Arg377Cys mutations are common among Moroccan patients with MPS I and MPS IIIA, respectively. The ability to detect these mutations using restriction endonucleases allows for molecular diagnosis in affected families. Five polymorphisms were identified among them four are novel.