AIM:To describe the clinical heterogeneity of patients with novel mutations in BEST1.METHODS:All the members in the two Chinese families underwent detailed clinical evaluations including best-corrected visual acuity,s...AIM:To describe the clinical heterogeneity of patients with novel mutations in BEST1.METHODS:All the members in the two Chinese families underwent detailed clinical evaluations including best-corrected visual acuity,slit-lamp examination,applanation tonometry,and dilated fundus examination.Fundus autofluorescence,fundus fluorescein angiography,spectral-domain optical coherence tomography,electrooculography,and electroretinogram were also performed.Genomic DNA was extracted from venous blood for all the participants.The targeted next-generation sequencing of inherited retinal disease-associated genes was conducted to identify the causative mutation.RESULTS:A novel BEST1 missense mutation c.41T>C(p.Leu14Ser) was identified in Family 1.It was co-segregated with the phenotype of best vitelliform macular dystrophy(BVMD) and bioinformatics analysis confirmed it was harmful.Another novel BEST1 frameshift mutation c.345_(3)46insGGCAAGGACG(p.Glu119Glyfs*116) and a novel USH2A missense mutation c.12560G>A,p.Arg4187 His were identified in family 2 with retinitis pigmentosa(RP),which might interact and lead to the phenotype of RP.CONCLUSION:Two novel mutations in the BEST1 gene in two unrelated families with distinct phenotypes and BEST1 mutation accompanied with USH2A mutation would result in RP,which could be enormously helpful in understanding the pathogenesis of the inherited retinal disease caused by a BEST1 mutation.展开更多
Objective:Autosomal recessive bestrophinopathy(ARB),a retinal degenerative disease,is characterized by central visual loss,yellowish multifocal diffuse subretinal deposits,and a dramatic decrease in the light peak on ...Objective:Autosomal recessive bestrophinopathy(ARB),a retinal degenerative disease,is characterized by central visual loss,yellowish multifocal diffuse subretinal deposits,and a dramatic decrease in the light peak on electrooculogram.The potential pathogenic mechanism involves mutations in the BEST1 gene,which encodes Ca2+-activated Cl−channels in the retinal pigment epithelium(RPE),resulting in degeneration of RPE and photoreceptor.In this study,the complete clinical characteristics of two Chinese ARB families were summarized.Methods:Pacific Biosciences(PacBio)single-molecule real-time(SMRT)sequencing was performed on the probands to screen for disease-causing gene mutations,and Sanger sequencing was applied to validate variants in the patients and their family members.Results:Two novel mutations,c.202T>C(chr11:61722628,p.Y68H)and c.867+97G>A,in the BEST1 gene were identified in the two Chinese ARB families.The novel missense mutation BEST1 c.202T>C(p.Y68H)resulted in the substitution of tyrosine with histidine in the N-terminal region of transmembrane domain 2 of bestrophin-1.Another novel variant,BEST1 c.867+97G>A(chr11:61725867),located in intron 7,might be considered a regulatory variant that changes allele-specific binding affinity based on motifs of important transcriptional regulators.Conclusion:Our findings represent the first use of third-generation sequencing(TGS)to identify novel BEST1 mutations in patients with ARB,indicating that TGS can be a more accurate and efficient tool for identifying mutations in specific genes.The novel variants identified further broaden the mutation spectrum of BEST1 in the Chinese population.展开更多
基金Supported by the Health Special Research Projects of Military Commission (No.19BJZ39)the Key Research Plan of Hainan Province (No.ZDYF2020031)。
文摘AIM:To describe the clinical heterogeneity of patients with novel mutations in BEST1.METHODS:All the members in the two Chinese families underwent detailed clinical evaluations including best-corrected visual acuity,slit-lamp examination,applanation tonometry,and dilated fundus examination.Fundus autofluorescence,fundus fluorescein angiography,spectral-domain optical coherence tomography,electrooculography,and electroretinogram were also performed.Genomic DNA was extracted from venous blood for all the participants.The targeted next-generation sequencing of inherited retinal disease-associated genes was conducted to identify the causative mutation.RESULTS:A novel BEST1 missense mutation c.41T>C(p.Leu14Ser) was identified in Family 1.It was co-segregated with the phenotype of best vitelliform macular dystrophy(BVMD) and bioinformatics analysis confirmed it was harmful.Another novel BEST1 frameshift mutation c.345_(3)46insGGCAAGGACG(p.Glu119Glyfs*116) and a novel USH2A missense mutation c.12560G>A,p.Arg4187 His were identified in family 2 with retinitis pigmentosa(RP),which might interact and lead to the phenotype of RP.CONCLUSION:Two novel mutations in the BEST1 gene in two unrelated families with distinct phenotypes and BEST1 mutation accompanied with USH2A mutation would result in RP,which could be enormously helpful in understanding the pathogenesis of the inherited retinal disease caused by a BEST1 mutation.
文摘Objective:Autosomal recessive bestrophinopathy(ARB),a retinal degenerative disease,is characterized by central visual loss,yellowish multifocal diffuse subretinal deposits,and a dramatic decrease in the light peak on electrooculogram.The potential pathogenic mechanism involves mutations in the BEST1 gene,which encodes Ca2+-activated Cl−channels in the retinal pigment epithelium(RPE),resulting in degeneration of RPE and photoreceptor.In this study,the complete clinical characteristics of two Chinese ARB families were summarized.Methods:Pacific Biosciences(PacBio)single-molecule real-time(SMRT)sequencing was performed on the probands to screen for disease-causing gene mutations,and Sanger sequencing was applied to validate variants in the patients and their family members.Results:Two novel mutations,c.202T>C(chr11:61722628,p.Y68H)and c.867+97G>A,in the BEST1 gene were identified in the two Chinese ARB families.The novel missense mutation BEST1 c.202T>C(p.Y68H)resulted in the substitution of tyrosine with histidine in the N-terminal region of transmembrane domain 2 of bestrophin-1.Another novel variant,BEST1 c.867+97G>A(chr11:61725867),located in intron 7,might be considered a regulatory variant that changes allele-specific binding affinity based on motifs of important transcriptional regulators.Conclusion:Our findings represent the first use of third-generation sequencing(TGS)to identify novel BEST1 mutations in patients with ARB,indicating that TGS can be a more accurate and efficient tool for identifying mutations in specific genes.The novel variants identified further broaden the mutation spectrum of BEST1 in the Chinese population.
