Analysis of phenotype and genotype in eight Chinese pedigrees with glanzmann thrombastheuia / 中华检验医学杂志

Objective To study the GPⅡb/Ⅲa gene mutations of eight glanzmann thrombasthenia(GT) pedigrees. Methods Responses of eight probands to different agonists were observed by platelet aggregation test and the amount of αⅡb and β3 was determined by flow cytometry. All the exons of Ⅱb and Ⅲ a genes were amplified by PCR followed by sequencing for mutational screening. Further analysis of the normal population excluded the possibility of mutational sites as a polymorphism. Results Eight probands showed normal PLT counts, dispersion of the platelet particles without aggregation, prolonged bleeding time and severely reduced platelet aggregation in response to the physiological agonists- ADP, epinephrine, and collagen, but relatively normal aggregation of PLT in response to ristocetin. Flow cytometry showed that all probande were Ⅰ type GT, except that proband 2 was Ⅲ type GT and proband 6 was Ⅱ type GT. The sequencing results showed that twelve different types mutations were present in eight probands, including GIOA, Gl412T, GII99A, 1525deiC, G2223T, C2671T, 2930delG, IVSI5 (-1) delG, A2334C, C1750T, 69-79del and CA70A. We were not able to detected any mutations in GP Ⅱb/Ⅲa gone on proband 3. Conclusions GT is mainly caused by GPⅡb/Ⅲa gene mutations. G10A, 69-79del, C470A,G1412T, G2223T, C2671T and 1525delC were the novel mutations causing GT.

Analysis of phenotype and genotype in three Chinese pedigrees with glanzmann thrombasthenia / 中华检验医学杂志

Objective To identify the gene mutations of platelet membrane glycoprotein Ⅱ b,Ⅲa(GPⅡb/Ⅲa)in three Chinese pedigrees with Glanzmann thrombastIlenia.Methods All exons and exonintron boundaries of GP Ⅱ b/Ⅲ a gene were amplified by PCR analysis followed by DNA sequencing.DNA sequencing was used to exclude gene polymorphisms.Results The probands in the three pedigrees had a normal platelet count,coagulation profiles,scattered platelets on the blood film,a prolonged cutaneous bleeding time,and impaired or minimal ex vivo platelet aggregation in response to ADP,thrombin,collagen,adrenaline and arachidonic acid,but normal platelet aggregation in response to ristoeetin.Both FACS and Western blotting demonstrated trace content of αⅡb in the platelets from proband 1 and proband 3,who were classified as type Ⅰ GT,and a small amount of αⅡb in the platelets from proband 2,who was classified as type Ⅱ GT.Compound heterozygous mutations,T2255G(Leu721Arg)and C2671T(Gln860Stop)were identified in proband 1.The proband 2 had homozygous A2334C(Gln747Pro)missense mutation.Nonsense mutations C1750T (Arg584Stop)and 69-79 deletion mutation were identified in proband 3. Conclusions Compound heterozygous mutations T2255G and C2671T of αⅡb gene lead to type Ⅰ Glanzmann thrombasthenia for proband 1. Homozygous mutation A2334C of αⅡb gene leads to type Ⅱ Glanzmann thrombasthenia for proband 2. Compound heterozygous mutations C1750T and 69-79del αⅡb gene lead to type Ⅰ Glanzmann thrombasthenia for proband 3. T2255G,C1671T and 69-79del aye novel mutations for αⅡb gene.

Study on methylation of the p73 gene in acute lymphoblastic leukemia and its clinical significances / 中国实用内科杂志

Objective To investigate the effects of methylation of p73 gene on pathogenesis of acute lymphoblastic leukemia.Methods The restriction endonuclease enzyme digestion combined with PCR was used to detect p73 gene and methylation in 42 patients with acute lymphoblastic leukemia.Results Methylation of p73 gene was found in 28.6%(12/42).Patients without methylation of p73 gene had a higher complete remission rate of first chemotherapy and a longer survival time than those with methylation of p73 gene.Conclusion Methylation of p73 gene probably plays a role in the pathogenesis of acute lymphoblastic leukemia and may have clinical significance in predicting prognosis of ALL.