Detection of alpha-thalassemia-1 Southeast Asian type using real-time gap-PCR with SYBR Green1 and high resolution melting analysis.

Alpha-thalassemia-1 Southeast Asian (SEA) type is the most common genetic disorder in the Asian population. Couples who are both carriers have a 25% chance of conceiving Bart's hydrops fetalis. Therefore, results from carrier screening and prenatal diagnosis frequently need to be available rapidly. A rapid technique for diagnosis of alpha-thalassemia-1 SEA type was implemented. The technique used is based on real-time gap-PCR and high resolution melting (HRM) analysis of the amplified fragment using the Rotor-Gene 6000. The DNA samples used for amplification were obtained from whole blood, cord blood, and chorionic villus sampling (CVS). With this method, the alpha-thalassemia-1 SEA allele can be easily distinguished from wild type alpha-globin gene allele. The real-time gap-PCR and HRM analysis offers additional benefits including minimal labor, rapid turnaround time, and a decreased risk of PCR carryover contamination. It is cost-effective and safe, does not require fluorescently labeled probe and hazardous chemicals. Moreover, it is accurate showing 100% concordance with conventional gap-PCR analysis.