Study of the Role of Genetic Modifiers in Hemoglobinopathies

Inclusion Criteria: * Clinical diagnosis of an inherited hemoglobinopathy, including sickle cell disease (SCD), β-thalassemia, and α-thalassemia; all genotypes will be considered. * Age ≥ 2 years old at the time of the collection of the phenotypic data. * There will be no limits on study participants in terms of gender, ethnicity, morbidities. Exclusion Criteria: * Patients treated with stem cell transplantation or genetic therapy. * Age \< 2 years old at the time of the collection of the phenotypic data. * Patient or legal representative for minors unwilling or unable to give consent.