Universal screening for hemoglobinopathies in today's multi-ethnic societies: How and when

Abstract

Increasing multi-ethnicity in countries endemic or non-endemic for hemoglobinopathies has brought fundamental changes to the screening strategies for these traits. While in the past pre-screening on microcytosis was a reasonable method to economize upon follow up analysis, selecting low mean corpuscular volume means today missing all those normocytic carriers of common traits associated with severe conditions. Therefore, blood count should not be considered as a pre-selection tool but as additional information to be used for the interpretation of the provisional results, obtained by routine high throughput separation and measurement of the hemoglobin (Hb) fractions. Moreover, the moment of screening should be well planned depending on the social and cultural situation. Screening for genetic diseases in a modern multi-ethnic society should be offered to couples seeking progeny when both partners are more likely to be equally concerned with the good health of their children. In several societies screening before marriage and changing partner choice is culturally accepted. However, new generations are bound to disagree with these more or less imposed conditions and may decide not to renounce the choice of their partner asking for other preventive methods. In addition, a carrier state during pre-marital screening may in some cultures stigmatize the carrier, mostly the female with adverse social consequences. Therefore, screening for hemoglobinopathies early in pregnancy is the most sensible alternative in modern countries. Adding hemoglobinopathies to the routine rhesus screening using a simple separation of the Hb fractions on dedicated devices (high performance liquid chromatography or capillary electrophoresis) will virtually identify all female carriers of all common traits responsible for the severe conditions mainly sickle cell disease and thalassemia major in time for partner analysis, counseling and primary prevention.

Keywords: Sickle cell disease; Thalassemia; Diagnosis; Prevention

Core tip: All women in most modern countries are offered screening for rhesus antagonism and infectious diseases early in pregnancy. Hemoglobinopathy (HBP) screening done together with rhesus screening using an inexpensive routine high performance liquid chromatography or capillary electrophoresis analysis could identify all women carriers of the frequent traits associated with the severe forms of HBP. Subsequent partner analysis could identify all couples at risk to be confirmed by molecular analysis in time for prenatal diagnosis when requested. This procedure will allow the prevention task to be offered at the most logical moment and by the most specialized hands of the gynecologists and obstetricians in collaboration with the local labs and the genetic counselors.