[Genetic study on 27 children with beta-thalassemia major and their parents in Sichuan area].
OBJECTIVE: This genetic analysis on 27 children with beta-thalassemia major and their parents was performed in an attempt to elucidate the characteristics of gene mutations, and to improve the early diagnosis and prevention of this disease in Sichuan area. METHODS: The hematologic studies of beta-thalassemia included the osmotic fragility of erythrocyte determined by brine osmosis method, the HbF qualitatively determined by one minute anti-alkaline method, the HbA2 assayed by acetyl-cellulose membrane electrophoresis and eluate photometric method, and the total hemoglobin measured by the ferric-cynade method. DNA was extracted from peripheral white blood cell with standard method (phenol-chloroform extract). Multiple allele specific polymerase chain reaction (MASPCR) was used for targeted DNA amplification and gene mutation analysis. RESULTS: It was found that the most common mutants in Sichuan area were CD17 (A-->T), CD41-42 (-TTCT) and IVS II -654 (C-->T). Their percentages were 43.64%, 36.36% and 14.54%, respectively. CONCLUSION: MASPCR method is a simple, effective and inexpensive method for genetic diagnosis of beta-thalassemia major. We identified 3 most common mutants in Sichuan by using MASPCR.