Methylmalonic aciduria（MMA） is a common inherited autosomal recessive disorder resulting from defects in the enzyme methylmalonyl CoA mutase（MCM,mut complementation group） or in the synthesis of the MCM cofactor a...Methylmalonic aciduria（MMA） is a common inherited autosomal recessive disorder resulting from defects in the enzyme methylmalonyl CoA mutase（MCM,mut complementation group） or in the synthesis of the MCM cofactor adenosylcobalamin（cbl complementation groups）.The defects in the mut complementation group accounts for the largest number of patients with isolated MMA.At least 200 mutations in the MUT gene on chromosome 6p12 have been identified in MMA patients until now.This study aimed to investigate the clinical characteristics of MMA and genomic variations in the MUT gene of Chinese patients.Genomic DNA was extracted from 18 patients who were diagnosed as having isolated MMA by gas chromatography/mass spectrometry（GC-MS）,and from some of their parents as well.Amplification and direct sequencing of the MUT coding regions（exon 2-13） and their adjacent intronic consensus splice sites were performed in order to identify the disease causing mutations.In this group,six novel mutations in the MUT gene,c.424AG（p.T142A）,c.786TG（p.S262R）,c.808GC（p.G270R）,c.1323_1324insA,c.1445-1GA and c.1676＋77AC were identified.p.T142A and p.G270R were respectively detected at a heterozygous level in one patient.Two previously reported mutations,c.682CT（p.R228X） and c.323GA（p.R108H） were also found in this study.In addition,six previously described single nucleotide polymorphism（SNP）,c.636AG（p.K212K）,c.1495GA（p.A499T）,c.1595AG（p.H532R）,c.1992GA（p.A664A）,c.2011GA（p.V671I） and c.1677-53AG were identified.In this study,we updated the spectrum of MUT mutations and identified the main MMA-causing mutations in Chinese MMA patients.展开更多
AIM： To establish and validate the mutation testing for identification and characterization of hereditary non-polyposis colorectal cancer （HNPCC） in suspected Chinese patients. METHODS： Five independent Chinese ki...AIM： To establish and validate the mutation testing for identification and characterization of hereditary non-polyposis colorectal cancer （HNPCC） in suspected Chinese patients. METHODS： Five independent Chinese kindreds with HNPCC fulfilling the classical Amsterdam criteria were collected. Genomic DNA was extracted after informed consent was obtained. The coding region of hMSH2 and hMLH1 genes was detected by polymerase chain reaction （PCR） and denaturing high-performance liquid chromatography （DHPLC）. Mutations identified in the proband by DHPLC were directly sequenced using a 377 DNA sequencer, analyzed with a basic local alignment tool （BLAST）, and tested in the corresponding family members by direct DNA sequencing. RESULTS： Mutations were identified in two Chinese HNPCC kindreds. One was the missense mutation of hMSH2 c.1808A→G resulting in Asp 603 Gly identified in the proband of the fifth HNPCC （HNPCCS） kindred. In the HNP5 kindred, three family members were found to have this mutation and two of them had colorectal cancer. The other mutation of hMLH1 c.1882A→G was identified in the HNP2 kindred＇s proband, which might be the nonsense mutation analyzed by BLAST. CONCLUSION： Pedigree investigation and mutation testing of hMSH2 and hMLH1 are the practical methods to identify high-risk HNPCC patients in China.展开更多
蝎毒镇痛活性肽Bm K Ang M1是从东亚钳蝎(Buthus martensii Karsch)蝎毒中分离得到的一种新型长链蝎毒素,其镇痛活性强且毒性低,有望开发成镇痛新药。本文将Bm K Ang M1基因转入毕赤酵母(Pichia pastoris)GS115,筛选得到甲醇利用缓慢型(...蝎毒镇痛活性肽Bm K Ang M1是从东亚钳蝎(Buthus martensii Karsch)蝎毒中分离得到的一种新型长链蝎毒素,其镇痛活性强且毒性低,有望开发成镇痛新药。本文将Bm K Ang M1基因转入毕赤酵母(Pichia pastoris)GS115,筛选得到甲醇利用缓慢型(Muts)和快速型(Mut+)的重组子;采用实时荧光定量PCR方法,检测了Mut+重组子中Bm K Ang M1基因的拷贝数,筛选出含单拷贝Bm K Ang M1基因的Mut+重组子;在相同培养条件下,比较了含单拷贝Bm K Ang M1基因的Muts和Mut+重组子表达Bm K Ang M1的水平。结果表明,Muts重组子中Bm K Ang M1基因转录水平是Mut+重组子的2.7倍,Muts重组子中Bm K Ang M1蛋白表达量是Mut+重组子的1.5倍。因此,Muts重组子比Mut+重组子具有更强的Bm K Ang M1表达能力。展开更多
基金supported by grants from the National Basic Research Program of China(2005CB522507)the 11th Five-year Plan of National Science & Technology(2006BAI05A07)
文摘Methylmalonic aciduria（MMA） is a common inherited autosomal recessive disorder resulting from defects in the enzyme methylmalonyl CoA mutase（MCM,mut complementation group） or in the synthesis of the MCM cofactor adenosylcobalamin（cbl complementation groups）.The defects in the mut complementation group accounts for the largest number of patients with isolated MMA.At least 200 mutations in the MUT gene on chromosome 6p12 have been identified in MMA patients until now.This study aimed to investigate the clinical characteristics of MMA and genomic variations in the MUT gene of Chinese patients.Genomic DNA was extracted from 18 patients who were diagnosed as having isolated MMA by gas chromatography/mass spectrometry（GC-MS）,and from some of their parents as well.Amplification and direct sequencing of the MUT coding regions（exon 2-13） and their adjacent intronic consensus splice sites were performed in order to identify the disease causing mutations.In this group,six novel mutations in the MUT gene,c.424AG（p.T142A）,c.786TG（p.S262R）,c.808GC（p.G270R）,c.1323_1324insA,c.1445-1GA and c.1676＋77AC were identified.p.T142A and p.G270R were respectively detected at a heterozygous level in one patient.Two previously reported mutations,c.682CT（p.R228X） and c.323GA（p.R108H） were also found in this study.In addition,six previously described single nucleotide polymorphism（SNP）,c.636AG（p.K212K）,c.1495GA（p.A499T）,c.1595AG（p.H532R）,c.1992GA（p.A664A）,c.2011GA（p.V671I） and c.1677-53AG were identified.In this study,we updated the spectrum of MUT mutations and identified the main MMA-causing mutations in Chinese MMA patients.
基金The Special Funds of China Education Ministry for Returnees, No. 2003-14
文摘AIM： To establish and validate the mutation testing for identification and characterization of hereditary non-polyposis colorectal cancer （HNPCC） in suspected Chinese patients. METHODS： Five independent Chinese kindreds with HNPCC fulfilling the classical Amsterdam criteria were collected. Genomic DNA was extracted after informed consent was obtained. The coding region of hMSH2 and hMLH1 genes was detected by polymerase chain reaction （PCR） and denaturing high-performance liquid chromatography （DHPLC）. Mutations identified in the proband by DHPLC were directly sequenced using a 377 DNA sequencer, analyzed with a basic local alignment tool （BLAST）, and tested in the corresponding family members by direct DNA sequencing. RESULTS： Mutations were identified in two Chinese HNPCC kindreds. One was the missense mutation of hMSH2 c.1808A→G resulting in Asp 603 Gly identified in the proband of the fifth HNPCC （HNPCCS） kindred. In the HNP5 kindred, three family members were found to have this mutation and two of them had colorectal cancer. The other mutation of hMLH1 c.1882A→G was identified in the HNP2 kindred＇s proband, which might be the nonsense mutation analyzed by BLAST. CONCLUSION： Pedigree investigation and mutation testing of hMSH2 and hMLH1 are the practical methods to identify high-risk HNPCC patients in China.
文摘蝎毒镇痛活性肽Bm K Ang M1是从东亚钳蝎(Buthus martensii Karsch)蝎毒中分离得到的一种新型长链蝎毒素,其镇痛活性强且毒性低,有望开发成镇痛新药。本文将Bm K Ang M1基因转入毕赤酵母(Pichia pastoris)GS115,筛选得到甲醇利用缓慢型(Muts)和快速型(Mut+)的重组子;采用实时荧光定量PCR方法,检测了Mut+重组子中Bm K Ang M1基因的拷贝数,筛选出含单拷贝Bm K Ang M1基因的Mut+重组子;在相同培养条件下,比较了含单拷贝Bm K Ang M1基因的Muts和Mut+重组子表达Bm K Ang M1的水平。结果表明,Muts重组子中Bm K Ang M1基因转录水平是Mut+重组子的2.7倍,Muts重组子中Bm K Ang M1蛋白表达量是Mut+重组子的1.5倍。因此,Muts重组子比Mut+重组子具有更强的Bm K Ang M1表达能力。
