Monilethrix, a congenital disease of hair, is usually associated with mutations in keratin genes, like KRT81, KRT83 and KRT86. We conducted this study to investigate the mutation of type Ⅱ human basic hair keratin hH...Monilethrix, a congenital disease of hair, is usually associated with mutations in keratin genes, like KRT81, KRT83 and KRT86. We conducted this study to investigate the mutation of type Ⅱ human basic hair keratin hHb/ KRT gene in a Han family with monilethrix and obtain information for potential pathogenic mechanism study of monilethrix. Peripheral blood samples were drawn for genomic DNA detection. Exon 1 and exon 7 of the KRT81, KRT83 and KRT86 genes were amplified by PCR. All PCR products were sequenced directly using an ABI 310 DNA sequencer. These sequences were aligned with the standard sequences in GenBank using the BLAST software. PCR products were digested with restriction endonuclease and restriction fragment length polymorphism （RFLP） analysis was performed. In this study, we identified one novel mutation, which is a heterozygous transitional mutation of G→A at position 1,289 in exon 7 of the KRT86 gene [R430Q （KRT86）]. RFLP assays for the novel mutation excluded the possibility of polymorphism. The R430Q mutation of the KRT86 gene may be pathogenic for monilethrix. Meanwhile, we did not find any novel mutation or recurrent mutation in exons 1 and 7 of KRT81 and KRT83 and exon 1 of KRT86. There is a potential pathogenic gene in the subjects and our results expand the spectrum of mutations in the hHb6 gene.展开更多
Objective： To investigate the gene polymorphism in a pedigree of congenital monilethrix. Methods： Genomic DNA of affected members, the normal members of the pedigree and 50 unrelated normal members who came from dif...Objective： To investigate the gene polymorphism in a pedigree of congenital monilethrix. Methods： Genomic DNA of affected members, the normal members of the pedigree and 50 unrelated normal members who came from different regions were extracted with a whole blood genomic DNA extraction kit and used as a template for the polymerase chain reaction （PCR）-mediated amplification of hHB1 and hHB6 genes. Results： In the pedigree, DNA analysis of patients and normal persons revealed C（447th） in exonl of hHB1 gene and the 52th codon was CCA encoding arginine. But it was a heteropeak of O or C in 50 unrelated normal members, which encodes glycine or arginine. It showed that this change was a single nucleotide polymorphisms （SNP）. Conclusion： A genetic heterogeneity of monilethrix exists in Chinese population. SNP which can result in the change of amino acid sequence is found in a pedigree of congenital monilethrix, and a genetic heterogeneity of monilethrix existed in Chinese population.展开更多
Background Monilethrix is an autosomal dominant hair disorder characterized clinically by alopecia and follicular papules.In this study,we collected a Han monilethrix family to detect the mutations in patients and inv...Background Monilethrix is an autosomal dominant hair disorder characterized clinically by alopecia and follicular papules.In this study,we collected a Han monilethrix family to detect the mutations in patients and investigated the correlation between the genotype and phenotype of monilethrix.Methods In this study,we identified a Chinese family with monilethrix through light microscopic and scanning electron microscopic （SEM） examination.Genomic DNA from peripheral blood samples was prepared.DNA samples from controls and monilethrix patients were subject to polymerase chain reaction （PCR） amplification.Two pairs of primers were used to amplify the seventh exon of KRT86.Mutation screening of the PCR products was detected using direct sequencing.Results Light microscopic examination showed a regular alternate enlargement and narrow area.SEM examination showed that part of the cuticle of the nodules shed and disappeared gradually in the narrow area with granular protrusions on the surface similar to the erosion-like structure.Parallel longitudinal ridge and groovepattern appeared,and the ridges varied in width,like dead wood.A heterozygous transversion mutation c.1204G＞A（p.E402K） in the seventh exon of KRT86 was identified in both patients.Conclusions The mutation of extron 7 of KRT86 identified plays a major role in the pathogenesis of this pedigree with monilethrix,and is a mutation hot spot of KRT86.Further research is needed to explore the relationship between the phenotype and the mutation of the type Ⅱ hair keratin gene KRT86 of monilethrix.展开更多
Monilehtrix is a rare inherited hair shaft disorder with considerable variations in age of onset severity and course. We present a 6-year-old girl with monilethrix and discuss different aspects of the disease and its ...Monilehtrix is a rare inherited hair shaft disorder with considerable variations in age of onset severity and course. We present a 6-year-old girl with monilethrix and discuss different aspects of the disease and its treatment.展开更多
基金supported by the National Natural Science Foundation of China (No. 30771947)Provincal Natural Science Foundation of Jiangsu (No. BK2007248)
文摘Monilethrix, a congenital disease of hair, is usually associated with mutations in keratin genes, like KRT81, KRT83 and KRT86. We conducted this study to investigate the mutation of type Ⅱ human basic hair keratin hHb/ KRT gene in a Han family with monilethrix and obtain information for potential pathogenic mechanism study of monilethrix. Peripheral blood samples were drawn for genomic DNA detection. Exon 1 and exon 7 of the KRT81, KRT83 and KRT86 genes were amplified by PCR. All PCR products were sequenced directly using an ABI 310 DNA sequencer. These sequences were aligned with the standard sequences in GenBank using the BLAST software. PCR products were digested with restriction endonuclease and restriction fragment length polymorphism （RFLP） analysis was performed. In this study, we identified one novel mutation, which is a heterozygous transitional mutation of G→A at position 1,289 in exon 7 of the KRT86 gene [R430Q （KRT86）]. RFLP assays for the novel mutation excluded the possibility of polymorphism. The R430Q mutation of the KRT86 gene may be pathogenic for monilethrix. Meanwhile, we did not find any novel mutation or recurrent mutation in exons 1 and 7 of KRT81 and KRT83 and exon 1 of KRT86. There is a potential pathogenic gene in the subjects and our results expand the spectrum of mutations in the hHb6 gene.
文摘Objective： To investigate the gene polymorphism in a pedigree of congenital monilethrix. Methods： Genomic DNA of affected members, the normal members of the pedigree and 50 unrelated normal members who came from different regions were extracted with a whole blood genomic DNA extraction kit and used as a template for the polymerase chain reaction （PCR）-mediated amplification of hHB1 and hHB6 genes. Results： In the pedigree, DNA analysis of patients and normal persons revealed C（447th） in exonl of hHB1 gene and the 52th codon was CCA encoding arginine. But it was a heteropeak of O or C in 50 unrelated normal members, which encodes glycine or arginine. It showed that this change was a single nucleotide polymorphisms （SNP）. Conclusion： A genetic heterogeneity of monilethrix exists in Chinese population. SNP which can result in the change of amino acid sequence is found in a pedigree of congenital monilethrix, and a genetic heterogeneity of monilethrix existed in Chinese population.
文摘Background Monilethrix is an autosomal dominant hair disorder characterized clinically by alopecia and follicular papules.In this study,we collected a Han monilethrix family to detect the mutations in patients and investigated the correlation between the genotype and phenotype of monilethrix.Methods In this study,we identified a Chinese family with monilethrix through light microscopic and scanning electron microscopic （SEM） examination.Genomic DNA from peripheral blood samples was prepared.DNA samples from controls and monilethrix patients were subject to polymerase chain reaction （PCR） amplification.Two pairs of primers were used to amplify the seventh exon of KRT86.Mutation screening of the PCR products was detected using direct sequencing.Results Light microscopic examination showed a regular alternate enlargement and narrow area.SEM examination showed that part of the cuticle of the nodules shed and disappeared gradually in the narrow area with granular protrusions on the surface similar to the erosion-like structure.Parallel longitudinal ridge and groovepattern appeared,and the ridges varied in width,like dead wood.A heterozygous transversion mutation c.1204G＞A（p.E402K） in the seventh exon of KRT86 was identified in both patients.Conclusions The mutation of extron 7 of KRT86 identified plays a major role in the pathogenesis of this pedigree with monilethrix,and is a mutation hot spot of KRT86.Further research is needed to explore the relationship between the phenotype and the mutation of the type Ⅱ hair keratin gene KRT86 of monilethrix.
文摘Monilehtrix is a rare inherited hair shaft disorder with considerable variations in age of onset severity and course. We present a 6-year-old girl with monilethrix and discuss different aspects of the disease and its treatment.
