The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform
Carl T Wittwer - One of the best experts on this subject based on the ideXlab platform.
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scanning the cystic fibrosis transmembrane conductance Regulator Gene using high resolution dna melting analysis
Clinical Chemistry, 2007Co-Authors: Jesse L Montgomery, Carl T Wittwer, Jana Kent, Luming ZhouAbstract:Background: Complete Gene analysis of the cystic fibrosis transmembrane conductance Regulator Gene ( CFTR ) by scanning and/or sequencing is seldom performed because of the cost, time, and labor involved. High-resolution DNA melting analysis is a rapid, closed-tube alternative for Gene scanning and genotyping. Methods: The 27 exons of CFTR were amplified in 37 PCR products under identical conditions. Common variants in 96 blood donors were identified in each exon by high-resolution melting on a LightScanner®. We then performed a subsequent blinded study on 30 samples enriched for disease-causing variants, including all 23 variants recommended by the American College of Medical Genetics and 8 additional, well-characterized variants. Results: We identified 22 different sequence variants in 96 blood donors, including 4 novel variants and the disease-causing p.F508del. In the blinded study, all 40 disease-causing heterozygotes (29 unique) were detected, including 1 new probable disease-causing variant (c.3500-2A>T). The number of false-positive amplicons was decreased 96% by considering the 6 most common heterozygotes. The melting patterns of most heterozygotes were unique (37 of 40 pairs within the same amplicon), the exceptions being p.F508del vs p.I507del, p.G551D vs p.R553X, and p.W1282X vs c.4002A>G. The homozygotes p.G542X, c.2789 + 5G>A, and c.3849 + 10kbC>T were directly identified, but homozygous p.F508del was not. Specific genotyping of these exceptions, as well as genotyping of the 5T allele of intron 8, was achieved by unlabeled-probe and small-amplicon melting assays. Conclusions: High-resolution DNA melting methods provide a rapid and accurate alternative for complete CFTR analysis. False positives can be decreased by considering the melting profiles of common variants.
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a comparison of high resolution melting analysis with denaturing high performance liquid chromatography for mutation scanning cystic fibrosis transmembrane conductance Regulator Gene as a model
American Journal of Clinical Pathology, 2005Co-Authors: Lanszu Chou, Elaine Lyon, Carl T WittwerAbstract:High-resolution melting analysis (HRMA) was compared with denaturing high-performance liquid chromatography (dHPLC) for mutation scanning of common mutations in the cystic fibrosis transmembrane conductance Regulator Gene. We amplified (polymerase chain reaction under conditions optimized for melting analysis or dHPLC) 26 previously genotyped samples with mutations in exons 3, 4, 7, 9, 10, 11, 13, 17b, and
Chunhua Lu - One of the best experts on this subject based on the ideXlab platform.
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pentaketide ansamycin microansamycins a i from micromonospora sp reveal diverse post pks modifications
Organic Letters, 2018Co-Authors: Jianxiong Wang, Haoxin Wang, Wen Li, Chunhua LuAbstract:Overexpression of the pathway-specific positive Regulator Gene mas13 activated the cryptic Gene cluster mas, resulting in the isolation of nine novel pentaketide ansamycins, namely, microansamycins A–I (1–9). These results not only revealed a biosynthetic Gene cluster of pentaketide ansamycins for the first time but also presented an unprecedented scenario of diverse post-PKS modifications in ansamycin biosynthesis.
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Pentaketide Ansamycin Microansamycins A–I from Micromonospora sp. Reveal Diverse Post-PKS Modifications
Organic Letters, 2018Co-Authors: Jianxiong Wang, Haoxin Wang, Wen Li, Chunhua LuAbstract:Overexpression of the pathway-specific positive Regulator Gene mas13 activated the cryptic Gene cluster mas, resulting in the isolation of nine novel pentaketide ansamycins, namely, microansamycins A–I (1–9). These results not only revealed a biosynthetic Gene cluster of pentaketide ansamycins for the first time but also presented an unprecedented scenario of diverse post-PKS modifications in ansamycin biosynthesis.
Carsten M. Pusch - One of the best experts on this subject based on the ideXlab platform.
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Population Haplotypes of Exon ORF15 of the Retinitis Pigmentosa GTPase Regulator Gene in Germany
Molecular Diagnosis & Therapy, 2006Co-Authors: Daniela Karra, Felix K. Jacobi, Martina Broghammer, Nikolaus Blin, Carsten M. PuschAbstract:Background: Mutations in exon ORF15 of the retinitis pigmentosa GTPase Regulator Gene (RPGR) within chromosomal region Xp21.1 are a significant cause of a number of retinal disorders. The high mutation rate is ascribed to the highly repetitive, purine-rich tracts within the exon ORF15 sequence. Importantly, all exon ORF15 mutations observed to date represent protein-truncating mutations (nonsense and frameshift mutations). Because of its repetitive motifs, mutation screening of the hot-spot region by direct DNA sequencing is a technically challenging task. Methods: We devised a screening strategy for exon ORF15 mutations that reserves DNA sequencing for precise sizing and base-order assessment of detected mutations. The screening strategy is based on a PCR/restriction fragment length polymorphism (RFLP) analysis of exon ORF15 and comparison with population-specific RFLP haplotypes. The latter were constructed from PCR/RFLP analysis of DNA samples from 100 healthy German male individuals. Mutational alterations of normal RFLP haplotype patterns were predicted. Results: Six distinct RFLP haplotypes (founder alleles H1-H6) were observed with frequencies ranging from 2% to 63%. All natural variations of exon ORF15 were in-frame alterations ranging in size between 3bp and 36bp. Prediction of mutation-specific RFLP patterns indicated a high detection rate of mutations. Conclusion: A new strategy has been developed using routine protocols for mutation screening of difficult-to-sequence, highly repetitive exon ORF15 of the RPGR Gene in a German population.
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Population haplotypes of exon ORF15 of the retinitis pigmentosa GTPase Regulator Gene in Germany : implications for screening for inherited retinal disorders.
Molecular diagnosis & therapy, 2006Co-Authors: Daniela Karra, Felix K. Jacobi, Martina Broghammer, Nikolaus Blin, Carsten M. PuschAbstract:Background: Mutations in exon ORF15 of the retinitis pigmentosa GTPase Regulator Gene (RPGR) within chromosomal region Xp21.1 are a significant cause of a number of retinal disorders. The high mutation rate is ascribed to the highly repetitive, purine-rich tracts within the exon ORF15 sequence. Importantly, all exon ORF15 mutations observed to date represent protein-truncating mutations (nonsense and frameshift mutations). Because of its repetitive motifs, mutation screening of the hot-spot region by direct DNA sequencing is a technically challenging task.
Jianxiong Wang - One of the best experts on this subject based on the ideXlab platform.
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pentaketide ansamycin microansamycins a i from micromonospora sp reveal diverse post pks modifications
Organic Letters, 2018Co-Authors: Jianxiong Wang, Haoxin Wang, Wen Li, Chunhua LuAbstract:Overexpression of the pathway-specific positive Regulator Gene mas13 activated the cryptic Gene cluster mas, resulting in the isolation of nine novel pentaketide ansamycins, namely, microansamycins A–I (1–9). These results not only revealed a biosynthetic Gene cluster of pentaketide ansamycins for the first time but also presented an unprecedented scenario of diverse post-PKS modifications in ansamycin biosynthesis.
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Pentaketide Ansamycin Microansamycins A–I from Micromonospora sp. Reveal Diverse Post-PKS Modifications
Organic Letters, 2018Co-Authors: Jianxiong Wang, Haoxin Wang, Wen Li, Chunhua LuAbstract:Overexpression of the pathway-specific positive Regulator Gene mas13 activated the cryptic Gene cluster mas, resulting in the isolation of nine novel pentaketide ansamycins, namely, microansamycins A–I (1–9). These results not only revealed a biosynthetic Gene cluster of pentaketide ansamycins for the first time but also presented an unprecedented scenario of diverse post-PKS modifications in ansamycin biosynthesis.
Daniela Karra - One of the best experts on this subject based on the ideXlab platform.
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Population Haplotypes of Exon ORF15 of the Retinitis Pigmentosa GTPase Regulator Gene in Germany
Molecular Diagnosis & Therapy, 2006Co-Authors: Daniela Karra, Felix K. Jacobi, Martina Broghammer, Nikolaus Blin, Carsten M. PuschAbstract:Background: Mutations in exon ORF15 of the retinitis pigmentosa GTPase Regulator Gene (RPGR) within chromosomal region Xp21.1 are a significant cause of a number of retinal disorders. The high mutation rate is ascribed to the highly repetitive, purine-rich tracts within the exon ORF15 sequence. Importantly, all exon ORF15 mutations observed to date represent protein-truncating mutations (nonsense and frameshift mutations). Because of its repetitive motifs, mutation screening of the hot-spot region by direct DNA sequencing is a technically challenging task. Methods: We devised a screening strategy for exon ORF15 mutations that reserves DNA sequencing for precise sizing and base-order assessment of detected mutations. The screening strategy is based on a PCR/restriction fragment length polymorphism (RFLP) analysis of exon ORF15 and comparison with population-specific RFLP haplotypes. The latter were constructed from PCR/RFLP analysis of DNA samples from 100 healthy German male individuals. Mutational alterations of normal RFLP haplotype patterns were predicted. Results: Six distinct RFLP haplotypes (founder alleles H1-H6) were observed with frequencies ranging from 2% to 63%. All natural variations of exon ORF15 were in-frame alterations ranging in size between 3bp and 36bp. Prediction of mutation-specific RFLP patterns indicated a high detection rate of mutations. Conclusion: A new strategy has been developed using routine protocols for mutation screening of difficult-to-sequence, highly repetitive exon ORF15 of the RPGR Gene in a German population.
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Population haplotypes of exon ORF15 of the retinitis pigmentosa GTPase Regulator Gene in Germany : implications for screening for inherited retinal disorders.
Molecular diagnosis & therapy, 2006Co-Authors: Daniela Karra, Felix K. Jacobi, Martina Broghammer, Nikolaus Blin, Carsten M. PuschAbstract:Background: Mutations in exon ORF15 of the retinitis pigmentosa GTPase Regulator Gene (RPGR) within chromosomal region Xp21.1 are a significant cause of a number of retinal disorders. The high mutation rate is ascribed to the highly repetitive, purine-rich tracts within the exon ORF15 sequence. Importantly, all exon ORF15 mutations observed to date represent protein-truncating mutations (nonsense and frameshift mutations). Because of its repetitive motifs, mutation screening of the hot-spot region by direct DNA sequencing is a technically challenging task.
