目的 :研究1例具有非典型临床特征的进行性骨化性纤维增殖不良症(fibrodysplasia ossificans progressiva,FOP)患者,并对其致病基因人活化蛋白/促激蛋白A受体1(activin A type 1 receptor,ACVR1)进行突变分析。方法:根据患者大踇趾轻微...目的 :研究1例具有非典型临床特征的进行性骨化性纤维增殖不良症(fibrodysplasia ossificans progressiva,FOP)患者,并对其致病基因人活化蛋白/促激蛋白A受体1(activin A type 1 receptor,ACVR1)进行突变分析。方法:根据患者大踇趾轻微畸形和进行性异位骨化等临床表现,结合骨骼系统放射线检查、骨ECT和相关血液生化检查进行临床诊断。采集患者、患者父母和60位正常人外周血,提取基因组DNA,对ACVR1基因全部外显子进行聚合酶链反应(polymerase chain reaction,PCR)扩增和序列分析;对突变后的蛋白质结构进行分子模拟以便评估其突变后的功能改变。结果:患者具有非典型的临床表现:先天性大踇趾轻微畸形和进行性非经典顺序的异位骨化,其父母无FOP相关临床表现。患者的ACVR1第5外显子存在c.774 G>C(R258S)杂合突变,而其父母和正常对照组均无此杂合突变。此外,患者和所有正常人都存在c.690 G>A(E230E),此为无意义突变。三维蛋白质分子模拟发现R258与高度保守的甘氨酸-丝氨酸(glycine-serine,GS)活化区邻近,该突变可能导致ACVR1与ACVR1的抑制蛋白FK506结合蛋白12(FK506 binding protein 12,FKBP12)结合的亲和力降低,进而对ACVR1抑制作用降低。结论:典型FOP均在ACVR1之GS区发生突变,而本例FOP在ACVR1激酶区发生突变,这可能是该患者在临床表现呈非典型的原因。该结果有助于我们更好地去理解FOP表型和基因型之间的关系。展开更多
Background We determined the diagnosis of hereditary hemorrhagic telangiectasis (HHT) in a suspected HHT family,identified ALK1 gene mutation and established a gene diagnosis method of HHT. The level of related plasma...Background We determined the diagnosis of hereditary hemorrhagic telangiectasis (HHT) in a suspected HHT family,identified ALK1 gene mutation and established a gene diagnosis method of HHT. The level of related plasma proteins (transforming growth factor β and thrombomodulin) were also analyzed.Methods Bleeding history and family history were collected; Dilatant nasal mucosal capillaries in proband were observed under nasal cavity endoscope; exons 3,7,8 of ALK1 gene in proband and her family members were amplified with polymerase chain reaction (PCR), and the PCR products were analyzed. Using enzyme-linked immunosorbent assay (ELISA),plasma TGF-β1 and TGF-β2 concentrations were measured. Plasma thrombomodulin (TM) level was detected by Western blotting.Results Of all family members,four had epstaxis,two had evident telangiectases on skin or mucosa. Gene screening results showed that C to T substitution at position 1231 in exon 8 of ALK1 gene (CGG→TGG) existed in proband,her affected brother and their father. The mutation did not exist in proband’s sister-in-law and nephew. Plasma TGF-β1 concentrations in the affected HHT was 20538,17194,13131 pg/ml,while that of normal control and unaffected family members was 15950,20297,12836 pg/ml,respectively. Plasma TGF-β2 in HHT patients was 14502,9550,10592 and that of normal controls 8579,20297,7680 pg/ml respectively. Level of plasma TM was in HHT subjects significantly lower than in normal subjects.Conclusions Chinese HHT individuals have mutant ALK1 gene,a C1231T variation on exon 8 of ALK1 is responsible for HHT clinical phenotypes in this family. ALK1 gene analysis,together with special clinical phenotypes and family history,provides a reliable method in diagnosing HHT. In affected HHT subjects,plasma TGFβ levels were not obviously different from those of normal subject; while plasma TM concentration was significantly lower than that in normal subjects. The significance and mechanism remain to be elucidated.展开更多
文摘目的 :研究1例具有非典型临床特征的进行性骨化性纤维增殖不良症(fibrodysplasia ossificans progressiva,FOP)患者,并对其致病基因人活化蛋白/促激蛋白A受体1(activin A type 1 receptor,ACVR1)进行突变分析。方法:根据患者大踇趾轻微畸形和进行性异位骨化等临床表现,结合骨骼系统放射线检查、骨ECT和相关血液生化检查进行临床诊断。采集患者、患者父母和60位正常人外周血,提取基因组DNA,对ACVR1基因全部外显子进行聚合酶链反应(polymerase chain reaction,PCR)扩增和序列分析;对突变后的蛋白质结构进行分子模拟以便评估其突变后的功能改变。结果:患者具有非典型的临床表现:先天性大踇趾轻微畸形和进行性非经典顺序的异位骨化,其父母无FOP相关临床表现。患者的ACVR1第5外显子存在c.774 G>C(R258S)杂合突变,而其父母和正常对照组均无此杂合突变。此外,患者和所有正常人都存在c.690 G>A(E230E),此为无意义突变。三维蛋白质分子模拟发现R258与高度保守的甘氨酸-丝氨酸(glycine-serine,GS)活化区邻近,该突变可能导致ACVR1与ACVR1的抑制蛋白FK506结合蛋白12(FK506 binding protein 12,FKBP12)结合的亲和力降低,进而对ACVR1抑制作用降低。结论:典型FOP均在ACVR1之GS区发生突变,而本例FOP在ACVR1激酶区发生突变,这可能是该患者在临床表现呈非典型的原因。该结果有助于我们更好地去理解FOP表型和基因型之间的关系。
基金ThisstudywassupportedbytheNationalNaturalScienceFoundationofChina (No 3 983 0 180 )
文摘Background We determined the diagnosis of hereditary hemorrhagic telangiectasis (HHT) in a suspected HHT family,identified ALK1 gene mutation and established a gene diagnosis method of HHT. The level of related plasma proteins (transforming growth factor β and thrombomodulin) were also analyzed.Methods Bleeding history and family history were collected; Dilatant nasal mucosal capillaries in proband were observed under nasal cavity endoscope; exons 3,7,8 of ALK1 gene in proband and her family members were amplified with polymerase chain reaction (PCR), and the PCR products were analyzed. Using enzyme-linked immunosorbent assay (ELISA),plasma TGF-β1 and TGF-β2 concentrations were measured. Plasma thrombomodulin (TM) level was detected by Western blotting.Results Of all family members,four had epstaxis,two had evident telangiectases on skin or mucosa. Gene screening results showed that C to T substitution at position 1231 in exon 8 of ALK1 gene (CGG→TGG) existed in proband,her affected brother and their father. The mutation did not exist in proband’s sister-in-law and nephew. Plasma TGF-β1 concentrations in the affected HHT was 20538,17194,13131 pg/ml,while that of normal control and unaffected family members was 15950,20297,12836 pg/ml,respectively. Plasma TGF-β2 in HHT patients was 14502,9550,10592 and that of normal controls 8579,20297,7680 pg/ml respectively. Level of plasma TM was in HHT subjects significantly lower than in normal subjects.Conclusions Chinese HHT individuals have mutant ALK1 gene,a C1231T variation on exon 8 of ALK1 is responsible for HHT clinical phenotypes in this family. ALK1 gene analysis,together with special clinical phenotypes and family history,provides a reliable method in diagnosing HHT. In affected HHT subjects,plasma TGFβ levels were not obviously different from those of normal subject; while plasma TM concentration was significantly lower than that in normal subjects. The significance and mechanism remain to be elucidated.
