ABSTRACT
Objective To investigate the prevalence and spectrum of β-thalassemia mutations in C, uangdong province, and provide a reference for prenatal diagnosis and genetic counseling in this population. Methods Three thousand two hundred and forty-seven blood samples were randomly selected from Guangzhou and 2984 blood samples from Shenzhen from January in 2005 to January in 2009. PCR and reverse dot blot hybridization (RDB) were adopted for detection of β-thalassemia mutations in Guangzhou and Shenzhen city. Results Seven hundred and fifty-one individuals in Guangzhou were found to have β-hemoglobin gene mutations, the detection rate was 23.13%(751/3247); 10 different mutations were identified, namely CD41-42(-TCTT), IVS-Ⅱ-654(C→T), -28(A→G), CDI7(A→T), CD71-72(+A), 13E, IVS-I-1(G→T), CD43(G→T), -29(A→G), CDI4-15(+G), which accounted for 42.53% (336/790) ,25.19% (199/790), 12.66% (100/790), 10.89% (86/790) ,3.29% (26/790), 2.15%(17/790), 1.27%( 10/790), 1.14%(9/790) ,0.51%(4/790) ,0.38%(3/790), respectively; the most common mutation was CD41-42(-TCTT), which accounted for 42.53%(336/790). In Shenzhen, 179 individuals were found to have β-thalassemia mutations, the detection rate was 6.00% (179/2984); 8 different mutations were identified excluding CD43 (G→T) and CD14-15 (+G); the most common mutation, however, was IVS-lI--654(C→T), which accounted for 40.44% (74/183). Conclusions The β-thalassemia mutations in Guangdong province are not only frequent, but also obviously heterogeneous, and the mutations differ from region to region. CD41-42 (-TCTT),ⅣS-Ⅱ-654(C→T), -28(A→G), CD17(A→T) were the 4 predominant mutations.
ABSTRACT
The aim of this study was to investigate the polymorphism of microsatellite repeats DXS15, CA13, CA22 tightly linked to FVIII gene in Guangdong population and its practical value in genetic diagnosis for hemophilia A. The polymerase chain reaction (PCR) and capillary electrophoresis (CE) methods were adopted to test the variability of the 3 microsatellite repeat in Guangdong females, including 111 females, 222 X chromosomes for detecting DXS15 polymorphism; 87 females, 174X chromosomes for detecting CA13 polymorphism; 94 females, 188 X chromosomes for detecting CA22 polymorphism. The results indicated that 11 alleles corresponding to DXS15 were found at this locus with size ranging from 140 to 160 bp. The polymorphism information content (PIC) of this microsatellite repeat was 0.82, heterozygosity was 82%. Six alleles corresponding to CA13 were found, with a size from 145 to 155 bp, and PIC was 0.56, heterozygosity was 56.2%. Four alleles corresponding to CA22 were found with size ranging from 79 to 85 bp, and PIC was 0.41, heterozygosity was 50%. It is concluded that in contrast to the information about Caucasian, the polymorphism of these 3 microsatellites differs from race to race, and region to region. DXS15, CA13 and CA22 are highly polymorphic genetic markers useful for linkage analysis of haemophilia A, which may play a vital role in detection and prenatal diagnosis for hemophilia A.