Abstract
α‐Thalassemia (thal) is one of the most common inherited disorders in the world and in Southern China. Three large deletions of the α‐globin gene, namely the − α3.7 and − α4.2 (single gene deletions), and − −SEA (Southeast Asian double gene deletion), are the main α‐thal abnormalities in Southern China. We have developed a reliable, single‐tube multiplex polymerase chain reaction (m‐PCR) assay for these three most frequently observed determinants in Southern China. By using this assay, we detected 40 α‐thal patients from Guangdong, Guangxi Province, and analyzed 116 blood samples from the Li ethnic group of Hainan Province. To our surprise, the combined incidence of − α3.7 and − α4.2 was found to be as high as 38.0% among the Li people, and the − α4.2 genotype is more frequent than − α3.7 in the Li people. No SEA deletions were found in the Li samples.