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Objective Aim to provide an effective genetic testing for thalassemia (thal) , we analyzed genotype α and β-globin, as well as the polymorphism of β-globin gene in Cantonese in recent years.Methods Using single-tube complex PCR to detect deletional α-thal, reverse dot blotting(RDB)/PCR to detect 3 kinds undeletional α-thal——αCS, αQS, αWSand 18 kinds β-thal mutations which are common seen among Chinese population, 454 cases from Guangdong were given thal genotype genetic diagnosis.Among the 454 cases, 142 cases were selected to study the polymorphismsingle nucleotide polymorphisms(SNPs) of β-globin gene through denaturing high-performance liquid chromatography (DHPLC) combining the whole gene sequencing.Results For 438 cases were diagnosed thalassemia, 246 cases for α-thal, 164 cases for β-thal, 28 cases α-thal compounding ββ-thal.In 246 α-thal cases, deletions, the dominant mutations, 257 cases were diagnosed αα/--SEA, 20 cases αα/-α3.7, 9 cases αα/-α4.2.In 164 β-thal cases, β-thal heterozygotes accounted for 92.7%(152/164), of which the main genotypes are CD41-42, IVS-Ⅱ-654,-28, CD17, dual heterozygotes and homozygotes accounted for 4.9% (8/164)and 2.4%(4/164) respectively.The result of β-globin gene screening via DHPLC combining with sequencing based on the result of RDB.Moreover, we also found 2 kinds of unreported SNPs, IVS-I-13G>A, IVS-II-310 T>C.In the tested samples, the frequency of 4 kinds SNP was high, among which 3 kinds SNPs——rs713040, rs10768683, rs1609812, were carded together.Conclusion 1.Thal gene diagnosis, in α-thal cases, the form of αα/--SEA accounted the major and CD41-42, IVS-Ⅱ-654,-28, CD17 are the main type of β-thal mutation.The frequency of β-thal heterozygotes, homozygotes, and α-thal combining β-thal is not low, especially α-thal combining β-thal easily lead to misdiagnosis in clinical tests, which is significant for genetic counseling and accurate prenatal diagnosis.2.DHPLC combining the whole β-globin gene sequencing can effectively detect the common β-thal mutation and even new mutations, SNPs.3.In Cantonese, the SNPs of β-globin gene, the frequency of rs713040, rs10768683, rs7480526, rs1609812 was high, and rs713040, rs10768683, rs1609812,especially,may exist genetic linkage.The further study about the linkage is needed by increasing sample size.