The method for thalassemia diagnosis was developed by genotyping thalassemia deletions, using multiplex polymerase chain reaction (PCR) followed by a melting curve analysis. Primers were designed to specifically amplify two deletion fragments, the SEA (South East Asia) and Thai deletions. The primers distinguished the thalassemia heterozygote from the homozygote, which cannot be diagnosed by standard hematological data and hemoglobin typing. Melting curve analysis was performed in 130 subjects in parallel with conventional gap-PCR analysis, and results showed 100% concordance.

Scientists led by Dr. Saovaros Svasti of Mahidol University (Nakhon Pathom, Thailand) developed the new and reliable assay for the diagnosis of α-thalassemia. The assay has high sensitivity and specificity, rapid turnaround time, and a decreased risk of contamination between samples. Prenatal screening and genetic counseling are essential for prevention and control of α-thalassemia. The current diagnostic assay is both labor-intensive and time-consuming.

Carriers of mutations in α-thalassemia might have some degree of protection against malaria, but children of parents who both carry the mutation α-thalassemia-1 can develop Hb Bart's hydrops fetalis, which results in fetal death in utero or soon after birth.

A report of the study appears in the May 1, 2010 issue of the Journal of Molecular Diagnostics. The authors suggest that this technique will "allow high throughput screening suitable for prevention and control of thalassemia in the Southeast Asia population."

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