Abstract: The methods, compositions and kits disclosed herein relate generally to the detection of nucleic acids and nucleic acid mutations, such as mutations that may be correlated with disease. More specifically, the methods, compositions and kits relate to the detection of mutations in the ?-globin gene cluster, to determining the gene dosage of ?-globin in a subject, and to diagnosing the subject based on the presence or absence of mutations and/or gene dosage determination.