【摘要】 目的:研究1个蛋白C(PC)和1个蛋白S(PS)缺陷症家系的表型诊断和基因特征。方法:PC活性(PC:A)和PS活性(PS:A)用发色底物法测定;PC抗原(PC:Ag)和PS抗原(PS:Ag)用ELISA方法测定。用PCR扩增PC和PS基因各个外显子及其侧翼序列,用直接测序法检测突变点。利用逆转录PCR(RT-PCR)分析PCmRNA水平变化。同时利用蛋白印迹分析血浆中PC含量的变化。结果:先证者1的PC:A为49%,PC:Ag为1.34mg/L,基因检测发现PC基因9号外显子的8831有G→A杂合无义突变,导致Trp372Stop;先证者2的PS:A为29%,PC:Ag为8.3mg/L,14号外显子Gln522(CAG)→Stop(TAG)。结论:G8831A杂合突变引起Trp372Stop,其可导致遗传性PC缺陷症;Gln522Stop可导致遗传性PS缺陷症。更多还原

【Abstract】 Objective To identify the mutation of a protein C (PC) and a protein S (PS) deficiency in two Chinese pedigrees. Methods The plasma levels of PC activity (PC:A), PC antigen (PC:Ag), PS activity (PS:A) and PS antigen (PS:Ag) of proband and two family members were detected using ELISA and chromogenic assay, respectively. All the exons and the intron-exon boundaries of PC gene and PS gene were analyzed by direct sequencing of the corresponding amplified PCR products in DNA from the proband. Reverse transcription PCR(RT-PCR) and Western blot were used to analyze the mRNA and protein in plasma. Results The plasma levels of PC:A and PC:Ag of proband 1 were 49% and 1.34 mg/L, respectively. A G8831A heterozygous mutation was detected in exon 9 of PC gene, resulting in the substitution of Trp for stop at the 372th amino acid. The levels of PS:A and PS:Ag of proband 2 were 29% and 8.3 mg/L, respectively. A nonsense mutation Gln522stop in exon 14 was detected in proband 2. Conclusions The G8831A heterozygous mutation in exon 9 of protein C gene, leads to hereditary PC deficiency. The Gln522 Stop causes PS deficiency.更多还原