title: Thalassaemia screening and confirmation of carriers in parents.
abstract: Haemoglobinopathies are among the most common inherited monogenic disorders worldwide. Thalassaemia screening for carrier status is recommended for adults of reproductive age if suspected of being at risk. Conventional laboratory methods for screening include the assessment of haematological indices, and high-performance liquid chromatography, capillary electrophoresis or isoelectric focusing to measure the levels of HbA2and HbF, and to identify haemoglobin variants. Each screening method has its advantages and disadvantages, the main disadvantage being that none can fully resolve all variants. The complex nature of the genetics of haemoglobinopathies necessitates expertise in the interpretation of screening results to evaluate the most likely genotypes, which must then be confirmed using the DNA diagnosis. This review highlights the limits and pitfalls of each screening technique, and outlines a rational combination of different methods to overcome issues in thalassaemia carrier detection.
authors.affiliation: Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, 10 Medical Drive, 117597, Singapore. Electronic address: obganb@nus.edu.sg.
authors.forename: Angela N
authors.initials: AN
authors.lastname: Barrett
authors.affiliation: 11-59, The Choolani Clinic, Mount Elizabeth Novena Hospital, 38 Irrawaddy Road, 329563, Singapore. Electronic address: sami@choolani.net.
authors.forename: Ramasamy
authors.initials: R
authors.lastname: Saminathan
authors.affiliation: Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Level 12 NUHS Tower Block, 1E Kent Ridge Road, 119228, Singapore. Electronic address: mahesh_a_choolani@nuhs.edu.sg.
authors.forename: Mahesh
authors.initials: M
authors.lastname: Choolani
mesh_terms: D002851:Chromatography, High Pressure Liquid; D019075:Electrophoresis, Capillary; D004909:Erythrocyte Indices; D005260:Female; D005319:Fetal Hemoglobin / Q000032:analysis / Q000235:genetics; D006580:Genetic Carrier Screening / Q000379:methods; D006443:Hemoglobin A2 / Q000032:analysis / Q000235:genetics; D006454:Hemoglobins / Q000032:analysis* / Q000235:genetics; D006579:Heterozygote; D006801:Humans; D007231:Infant, Newborn; D007525:Isoelectric Focusing; D008297:Male; D008403:Mass Screening; D015997:Neonatal Screening; D010290:Parents; D016742:Preconception Care; D011247:Pregnancy; D011296:Prenatal Diagnosis; D017085:alpha-Thalassemia / Q000175:diagnosis* / Q000235:genetics; D017086:beta-Thalassemia / Q000175:diagnosis* / Q000235:genetics
chemical_list: D006454:Hemoglobins; D006443:Hemoglobin A2; D005319:Fetal Hemoglobin
keywords: HbA2; carrier screening; haemoglobinopathy; red blood cell indices; thalassaemia trait