Beta thalassemia is an autosomal recessive condition characterized by decreased or absent synthesis of beta-globin chains due to sequence variants in the beta-globin gene (HBB). There are 3 main classes of beta thalassemia: Beta thalassemia trait (also called beta thalassemia minor and beta thalassemia carrier),   Beta thalassemia intermedia &  Beta thalassemia major.

Beta thalassemia trait is typically a harmless condition with varying degrees of microcytosis and hypochromia and sometimes mild anemia. Transfusions are not required. Beta thalassemia intermedia is a clinical distinction and is characterzied by a more severe degree of anemia than beta thalassemia trait with few or intermittent transfusions required. Later in life, these individuals are at risk for iron overload even in the absence of chronic transfusion due to increased intestinal absorption of iron. Beta thalassemia major typically comes to medical attention early in life due to severe anemia, hepatosplenomegaly, and failure to thrive. Skeletal changes are also common due to expansion of the bone marrow. Without appropriate treatment these patients have a shortened lifespan.

The majority of beta thalassemia variations (>90%) are point alterations, small deletions, or insertions, while the remaining are either due to large genomic deletions of HBB or, very rarely, trans-acting beta thalassemia variations located outside of the beta-globin gene cluster. This test detects almost all beta thalassemia sequence variants, as well as 619bp deletion, the most common gene deletion found among Sri Lankans.