Clinical and Molecular Profile of Dystrophin Gene Deletions in Eastern Morocco

Dystrophinopathies are genetic muscular disorders with recessive inheritance linked to the X chromosome due to mutations in the dystrophin gene, the <em>DMD</em> gene located in Xp21. The best-known forms are Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). Our study aims to determine the molecular profile and genotype/phenotype correlations of dystrophinopathies in the eastern region of Morocco. We report patients referred for 4 years (2020-2023) to the Medical Genetics Laboratory of the Mohammed VI University Hospital in Oujda for suspected dystrophinopathy and confirmed by a genetic study of the <em>DMD</em> gene using the PCR- Multiplex technique. A total of 15 patients were recruited. They had a mean age of 7.3 years at diagnosis, with a mean age of symptom onset of 3.37 years. Consanguinity was estimated at 46.66%, with 13.33% of familial forms. All patients have a DMD phenotype; calf hypertrophy was present in 86.66% of cases, a positive GOWERS sign, and elevated CK levels were present in all patients. Analysis of the <em>DMD</em> gene using the PCR-Multiplex technique showed that 80% of deletions are located in the central region of the gene, exon 50 being the most frequently deleted. 80% of patients had a deletion disrupting the reading frame, and the genotype/phenotype correlation in these cases was explained by the Monaco rule. The molecular analysis of the <em>DMD</em> gene is essential for accurate diagnosis, appropriate genetic counseling, and improved patient care. The PCR-Multiplex technique remains a good first-line strategy in the public health system, with a good cost/benefit ratio, enabling the detection of large deletions by analyzing the most frequently deleted exons.<strong> </strong>Dystrophinopathies represent a frequent reason for requesting genetic analysis in our practice. Multiplex PCR being a simple, rapid, non-invasive and cost-effective tool allowed us to provide a molecular description of this pathology in Eastern Morocco.