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Objective:To evaluate the possibility of the technology involving PEP and RDB for detecting β-thalassaemia multipoint mutations from a single cell simultaneously. Methods: A set of allele specific oligonucleotide (ASO) probes used for detecting 8 familiar β-thalassaemia mutations (CD41-42, IVS- Ⅱ -654, CD17, TATA box nt-28, CD71-72, TATA box nt-29, CD26, IVS- Ⅰ -5) were immobilized on a strip of nylon membrane. The genome of a individual cell was amplified by primer extension preamplification (PEP) with the mixture of15-base random oligonucleotides. The aliquots from PEP were used to amplify the objective gene fractions of β-thalassaemia gene by nested or semi-nested PCR. The membrane was hybridized with the final amplified products and then treated with Streptavidin-HRP and color development.Results :Totally 30 lymphocytes were picked up from blood samples of 1 healthy female and 4 patients with known β-thalassaemia mutations respectively. Each single lymphocyte was lysed in the proteinase K buffer. The amplification efficacy was 94.0% and alle drop-out(ADO) rate was 8.0%. Revert dot blot (RDB) was applied to the final amplified products from the 5 participants. The results of diagnosis were the same to the expected, and their genotypes were N/N, CD17 (A→T)/N, IVS- Ⅱ -654(C→T)/CD17(A → T), CD41-42 (-CTTT)/N and TATA box nt-28 (A→G)/N, respectively. Conclusion: The technology involving PEP and RDB could detectmultiple β-thalassaemia mutations from a single cell simultaneously,and the research provides experimental evidences for the feasibility of applying PEP and DNA array technology to screening multiple genetic mutations from a single cell, and will be applied to preimplantation genetic diagnosis and non-invasive prenatal diagnosis for β-thalassaemia.