Alpha-Thalassemia in North Morocco: Prevalence and Molecular Spectrum

Unlike the other hemoglobinopathies, few researches have been published concerning -thalassemia in Morocco. The epidemiological features and the mutation spectrum of this disease are still unknown. This regional newborn screening is the first to study -thalassemia in the north of Morocco. During the period from January 2015 to December 2016, 1658 newborns umbilical blood samples were investigated. Suspected newborns were screened for -globin defects using Gap-PCR and Multiplex Ligation-dependent Probe Amplification technique. The prevalence of -thalassemia, its mutation spectrum, and its allelic frequencies were described for the first time in Morocco. Six different -globin genetic disorders were detected in 16 neonates. This screening valued the prevalence of -thalassemia in the studied population at 0.96% and showed the wide mutation spectrum and the heterogeneous geographical distribution of the disease. A high rate of carriers was observed in Laouamra, a rural commune in Larache province. Heterogeneity of -globin alleles in Morocco explains the high variability of -thalassemia severity. This diversity reflects the anthropological history of the country. These results would contribute to the prevention of thalassemia in Morocco directing the design of a nationwide screening strategy and awareness campaign.