Background Mutations in fumarylacetoacetate hydrolase （FAH） gene can lead to tyrosinemia type 1 （HT1）, a relatively rare autosomal recessive disorder. To date, no molecular genetic defects of HT1 in China have bee...Background Mutations in fumarylacetoacetate hydrolase （FAH） gene can lead to tyrosinemia type 1 （HT1）, a relatively rare autosomal recessive disorder. To date, no molecular genetic defects of HT1 in China have been described. We investigated a Chinese family with a HT1 child to identify mutations in FAH. Methods DNA sequencing was used for mutations screening in FAH gene. Real-time polymerase chain reaction （PCR） was performed to determine the FAH gene expression level. To confirm the presence of degradation by the nonsense-mediated mRNA decay pathway （NMD）, the fragments containing R237X mutations were analyzed by primer introduced restriction analysis-polymerase chain reaction （PIRA-PCR） and cDNA sequencing. Finally, the effects of the mutations reported in this study were predicted by online softwares. Results A boy aged 3 years and 8 months was diagnosed clinically with HT1 based on his manifestations and biochemical abnormalities. Screening of FAH gene revealed two heterozygous mutations R237X and L375P transmitted from his mother and father respectively. In this pedigree, the amount of FAH mRNA relative to a healthy control was 0.44 for the patient, 0.77 for his mother and 1.07 for his father. Moreover, both PIRA-PCR and cDNA sequencing showed significant reduction of the FAH mRNA with R237X nonsense mutation. The missense mutation of L375P was not reported previously and prediction software showed that this mutation decreased the stability of protein structure and affected protein function. Conclusions This is the first case of HT1 analyzed by molecular genetics in China. The R237X mutation in FAH down- regulates the FAH gene expression, and the L375P mutation perhaps interrupts the secondary structure of FAH protein.展开更多
In this study the kit gene was amplified from total brain RNA of W-3Bao heterozygote and normal C57BL/6 mice by RT-PCR followed by sequencing.To validate the mutation found in mRNA,the corresponding genome sequence wa...In this study the kit gene was amplified from total brain RNA of W-3Bao heterozygote and normal C57BL/6 mice by RT-PCR followed by sequencing.To validate the mutation found in mRNA,the corresponding genome sequence was amplified and sequenced.The results showed that there was a T-to-A transversion at the 441st nucleotide in W-3Bao ORF.The mutation introduces a pre-termination codon of amino acid and causes the phenotype of dominant white spot.展开更多
Background The clinical use of gentamicin always lies in its antimicrobial activity in the past as an aminoglycoside antibiotic.However,in the past decade,there were considerable interests in therapeutic approaches in...Background The clinical use of gentamicin always lies in its antimicrobial activity in the past as an aminoglycoside antibiotic.However,in the past decade,there were considerable interests in therapeutic approaches in treating hereditary diseases.Some of the genodermatosis is caused by nonsense mutations that create premature termination codons and lead to the production of truncated or non-functional proteins.Gentamicin could induce readthrough of nonsense mutations and enable the synthesis of full-length proteins.We focus on previous publications on topical application of gentamicin and review its utility in genetic skin diseases.Data sources We search the MEDLINE through PubMed,EMBASE databases,and the Clinical Trials Registry Platform from January 1960 to July 2020 using the key search terms"gentamicin,topical gentamicin,genodermatosis,genetic skin diseases".Results The application of gentamicin in genodermatosis yielded promising results,both in vivo and in vitro,including Nagashima-type palmoplantar keratosis,epidermolysis bullosa,Hailey-Hailey disease,hereditary hypotrichosis simplex of the scalp,etc.Conclusions Topical gentamicin is a potential treatment option for genodermatosis caused by nonsense mutation.展开更多
Suppressor tRNAs are engineered or naturally occurring transfer RNA molecules that have shown promise in gene therapy for diseases caused by nonsense mutations,which result in premature termination codons(PTCs)in codi...Suppressor tRNAs are engineered or naturally occurring transfer RNA molecules that have shown promise in gene therapy for diseases caused by nonsense mutations,which result in premature termination codons(PTCs)in coding sequence,leading to truncated,often nonfunctional proteins.Suppressor t RNAs can recognize and pair with these PTCs,allowing the ribosome to continue translation and produce a full-length protein.This review introduces the mechanism and development of suppressor t RNAs,compares suppressor tRNAs with other readthrough therapies,discusses their potential for clinical therapy,limitations,and obstacles.We also summarize the applications of suppressor tRNAs in both in vitro and in vivo,offering new insights into the research and treatment of nonsense mutation diseases.展开更多
文摘Background Mutations in fumarylacetoacetate hydrolase （FAH） gene can lead to tyrosinemia type 1 （HT1）, a relatively rare autosomal recessive disorder. To date, no molecular genetic defects of HT1 in China have been described. We investigated a Chinese family with a HT1 child to identify mutations in FAH. Methods DNA sequencing was used for mutations screening in FAH gene. Real-time polymerase chain reaction （PCR） was performed to determine the FAH gene expression level. To confirm the presence of degradation by the nonsense-mediated mRNA decay pathway （NMD）, the fragments containing R237X mutations were analyzed by primer introduced restriction analysis-polymerase chain reaction （PIRA-PCR） and cDNA sequencing. Finally, the effects of the mutations reported in this study were predicted by online softwares. Results A boy aged 3 years and 8 months was diagnosed clinically with HT1 based on his manifestations and biochemical abnormalities. Screening of FAH gene revealed two heterozygous mutations R237X and L375P transmitted from his mother and father respectively. In this pedigree, the amount of FAH mRNA relative to a healthy control was 0.44 for the patient, 0.77 for his mother and 1.07 for his father. Moreover, both PIRA-PCR and cDNA sequencing showed significant reduction of the FAH mRNA with R237X nonsense mutation. The missense mutation of L375P was not reported previously and prediction software showed that this mutation decreased the stability of protein structure and affected protein function. Conclusions This is the first case of HT1 analyzed by molecular genetics in China. The R237X mutation in FAH down- regulates the FAH gene expression, and the L375P mutation perhaps interrupts the secondary structure of FAH protein.
文摘In this study the kit gene was amplified from total brain RNA of W-3Bao heterozygote and normal C57BL/6 mice by RT-PCR followed by sequencing.To validate the mutation found in mRNA,the corresponding genome sequence was amplified and sequenced.The results showed that there was a T-to-A transversion at the 441st nucleotide in W-3Bao ORF.The mutation introduces a pre-termination codon of amino acid and causes the phenotype of dominant white spot.
基金supported by Children's Medicine Research Project of Beijing Children's Hospital,Capital Medical University(YZZD202002).
文摘Background The clinical use of gentamicin always lies in its antimicrobial activity in the past as an aminoglycoside antibiotic.However,in the past decade,there were considerable interests in therapeutic approaches in treating hereditary diseases.Some of the genodermatosis is caused by nonsense mutations that create premature termination codons and lead to the production of truncated or non-functional proteins.Gentamicin could induce readthrough of nonsense mutations and enable the synthesis of full-length proteins.We focus on previous publications on topical application of gentamicin and review its utility in genetic skin diseases.Data sources We search the MEDLINE through PubMed,EMBASE databases,and the Clinical Trials Registry Platform from January 1960 to July 2020 using the key search terms"gentamicin,topical gentamicin,genodermatosis,genetic skin diseases".Results The application of gentamicin in genodermatosis yielded promising results,both in vivo and in vitro,including Nagashima-type palmoplantar keratosis,epidermolysis bullosa,Hailey-Hailey disease,hereditary hypotrichosis simplex of the scalp,etc.Conclusions Topical gentamicin is a potential treatment option for genodermatosis caused by nonsense mutation.
基金supported by the National Natural Science Foundation of China(82371861)Key R&D Program of Zhejiang(2024SSYS0020)+1 种基金Henan Province Key Research and Promotion Project(242102311023)the Starting Fund from Zhejiang University。
文摘Suppressor tRNAs are engineered or naturally occurring transfer RNA molecules that have shown promise in gene therapy for diseases caused by nonsense mutations,which result in premature termination codons(PTCs)in coding sequence,leading to truncated,often nonfunctional proteins.Suppressor t RNAs can recognize and pair with these PTCs,allowing the ribosome to continue translation and produce a full-length protein.This review introduces the mechanism and development of suppressor t RNAs,compares suppressor tRNAs with other readthrough therapies,discusses their potential for clinical therapy,limitations,and obstacles.We also summarize the applications of suppressor tRNAs in both in vitro and in vivo,offering new insights into the research and treatment of nonsense mutation diseases.
