[Multiplex PCR for detecting genotypes of deletional alpha-thalassemia]

To investigate the clinical application of multiplex PCR in detecting genotypes of deletional alpha-thalassemia in South China and observe the distribution frequency of alpha-globin gene deletion, 145 patients with silent carrier, alpha thalassemia trait or HbH were identified by M-PCR and 1.2% agarose gel electrophoresis. There are 1.3, 1.6, 1.8 and 2.0 kb bands which indicate --(SEA), -alpha(4.2), alphaalpha and -alpha(3.7), respectively. The results showed that among 145 patients, 100 patients with --(SEA)/alphaalpha (68.9%), 15 with -alpha(3.7)/alphaalpha (10.3%), 8 with -alpha(4.2)/alphaalpha (5.52%), 2 with -alpha(3.7)/-alpha(4.2) (1.38%), 1 with -alpha(3.7)/-alpha(3.7) (0.69%), 1 with -alpha(4.2)/-alpha(4.2) (0.69%), 14 with --(SEA)/-alpha(3.7) (9.65%), 2 with --(SEA)/-alpha(4.2) (1.38%) were found. Two patients prenatal diagnosed were confirmed with Bart's hydrops fetuses. In conclusion, M-PCR analysis is a simple, rapid and accurate method for detection of alpha-thalassemia gene deletion. This technique is helpful in screening, carrier identification and prenatal diagnosis of deletional alpha-thalassemia.