Prevalence of Sickle Cell Disease in Mediterranean Populations
Sickle cell disease occurs in Mediterranean populations, though at lower rates than in African populations, with the condition affecting people from Mediterranean regions including Italy, Greece, and other Southern European countries. 1, 2
Geographic Distribution and Origin
- Thalassemia major originated in Mediterranean, Middle Eastern, and Asian regions, while sickle cell disease originated from throughout central Africa. 1
- However, due to migration patterns, both diseases now occur globally and represent a growing health problem in many countries. 1
- SCD predominantly affects people of African or Caribbean background (98% in UK registry), but also occurs in families from the Middle East, India, and Mediterranean regions. 2
Specific Prevalence Data
While the evidence provided does not give exact prevalence rates for Mediterranean populations specifically, the following context is important:
- The HbS mutation that causes sickle cell disease confers protection against malarial infection in heterozygous carriers, which led to high frequency of HbS in individuals of African and Mediterranean ancestry. 3
- Variations in the G6PD gene (related to hemoglobinopathies) are found in high frequency in African as well as Mediterranean and Asiatic populations, with patterns consistent with recent positive selection due to malaria pressure. 1
- In the European cohort of the CASiRe international study, 8% of SCD patients were Caucasian, including 21% of the Italian patients, demonstrating that Mediterranean Europeans do have SCD. 4
Clinical Implications
- Mediterranean people with SCD are affected by the same disease manifestations as other populations, including painful vaso-occlusive crises, stroke risk, chronic hemolytic anemia, and progressive multi-organ damage. 2, 5
- The genetic mutation is the same across populations—a C to A substitution at codon 6 of the beta globin gene, replacing glutamic acid with valine, creating abnormal hemoglobin S (HbS). 2
Important Caveats
- The constantly growing incidence of sickle cell disease in Mediterranean areas is also caused by recent migrations, which has induced the World Health Organization to pressure national health systems to strengthen prevention programs. 6
- Exact prevalence rates for Mediterranean populations are not well-documented in the literature, as most epidemiological studies focus on African and African-descended populations where the disease burden is highest. 5, 3