AIM：To summarize the phenotypes and identify the underlying genetic cause of the CRYBB1 and CRYBB2 gene responsible for congenital cataract in two Chinese families.METHODS：Detailed family histories and clinical data...AIM：To summarize the phenotypes and identify the underlying genetic cause of the CRYBB1 and CRYBB2 gene responsible for congenital cataract in two Chinese families.METHODS：Detailed family histories and clinical data were collected from patients during an ophthalmologic examination. Of 523 inheritable genetic vision systemrelated genes were captured and sequenced by targeted next-generation sequencing,and the results were confirmed by Sanger sequencing. The possible functional impacts of an amino acid substitution were performed with Poly Phen-2 and SIFT predictions.RESULTS：The patients in the two families were affected with congenital cataract. Sixty-five （FAMILY-1） and sixty two （FAMILY-2） single-nucleotide polymorphisms and indels were selected by recommended filtering criteria.Segregation was then analyzed by applying Sanger sequencing with the family members. A heterozygous CRYBB1 mutation in exon 4 （c.347T〉C, p.L116P） was identified in sixteen patients in FAMILY-1. A heterozygous CRYBB2 mutation in exon 5 （c.355G〉A, p.G119R） was identified in three patients in FAMILY-2. Each mutation cosegregated with the affected individuals and did not exist in unaffected family members and 200 unrelated normal controls.The mutation was predicted to be highly conservative and to be deleterious by both PolyPhen-2 and SIFT.CONCLUSION：TheCRYBB1 mutation（c.347T〉C）and CRYBB2 mutation （c.355G〉A） are novel in patients with congenital cataract. We summarize the variable phenotypes among the patients, which expanded the phenotypic spectrum of congenital cataract in a different ethnic background.展开更多
Genetic alterations are a major cause of microphthalmos,while novel-related genes and mutations in microphthalmos have rarely been explored.To identify the underlying genetic defect responsible for microphthalmos eyes...Genetic alterations are a major cause of microphthalmos,while novel-related genes and mutations in microphthalmos have rarely been explored.To identify the underlying genetic defect responsible for microphthalmos eyes in two three-generation Chinese families,we screened 425 genes involved in common inherited non-syndromic eye diseases with next-generation sequencing-based target capture sequencing of the two probands of two three-generation Chinese families diagnosed with microphthalmos.Variants were filtered and analyzed to identify possible disease-causing variants before Sanger sequencing validation.We enrolled two families with microphthalmos(Family 1:microphthalmos with congenital ocular coloboma and Family 2:simple microphthalmos).Two novel heterozygous mutations,Peroxidasin(PXDN)c.3165C>T(p.Pro1055Pro)and PXDN c.2640C>G(p.Arg880Arg),were found in Family 1,and Crystallin Beta B2(CRYBB2)c.481G>A(p.Gly161Arg)was found in Family 2,but none of the mutations were found in the unaffected individuals,who were phenotypically nor-mal.Multiple orthologous sequence alignment(MSA)revealed that the CRYBB2 p.Gly161Arg mutation was a deleterious effect mutation.In conclusion,the three novel mutations found in our study extend our current understanding of the genetic basis of microphthalmos and provide early pre-symptomatic diagnosis and emphasize the significance of genetic diagnosis of microphthalmos.展开更多
PURPOSE. To study some functional candidate genes in cataract families of Indi an descent. METHODS. Nine Indian families, clinically documented to have congeni tal/childhood cataracts, were screened for mutations in c...PURPOSE. To study some functional candidate genes in cataract families of Indi an descent. METHODS. Nine Indian families, clinically documented to have congeni tal/childhood cataracts, were screened for mutations in candidate genes such as CRYG (A→D), CRYBB2, and GJA8 by PCR analyses and sequencing. Genomic DNA sample s of either probands or any representative affected member of each family were P CR amplified and sequenced commercially. Documentation of single nucleotide poly morphisms (SNPs) and candidate mutations was done through BLAST SEARCH(http://ww w.ncbi.nlm.nih.gov/ blast/Blast.- cgi?). RESULTS. Several single nucleotide polymorphisms in CRYG, CRYBB2, and G JA8 genes were observed. Because they do not co-segregate with the phenotype, t hey were excluded as candidates for the cataract formation in these patients. However, a substitution (W151C in exon 6 of CRYBB2) was identi fied as the most likely causative mutation underlying the phenotype of central n uclear cataract in all affected members of family C176. Protein structural inter pretations demonstrated that no major structural alterations could be predicted and that even the hydrogen bonds to the neighboring Leu166 were unchanged. Surpr isingly, hydropathy analysis of the mutant βB2-crystallin featuring the amino acids at position 147 to 155, further increased the hydrophobicity, which might impair the solubility of the mutant protein. Finally, the Cys residue at positio n 151 might possibly be involved in intramolecular disulphide bridges with other cysteines during translation, possibly leading to dramatic structural changes. CONCLUSIONS. Exon 6 of CRYBB2 appears to be a critical region susceptible for mu tations leading to lens opacity.展开更多
基金Supported by China Postdoctoral Science Foundation Funded Project(No.2017M612211)Shandong Provincial Natural Science Foundation(No.ZR2018MH016)+3 种基金Qingdao Postdoctoral Application Research Project(No.40518060071)Medical Program of Shandong Province(No.2016WS0265)Qingdao Science and Technology Plan(No.16-6-2-14-nsh)Shandong Province Higher Educational Science and Technology Program(No.J17KA235)
文摘AIM：To summarize the phenotypes and identify the underlying genetic cause of the CRYBB1 and CRYBB2 gene responsible for congenital cataract in two Chinese families.METHODS：Detailed family histories and clinical data were collected from patients during an ophthalmologic examination. Of 523 inheritable genetic vision systemrelated genes were captured and sequenced by targeted next-generation sequencing,and the results were confirmed by Sanger sequencing. The possible functional impacts of an amino acid substitution were performed with Poly Phen-2 and SIFT predictions.RESULTS：The patients in the two families were affected with congenital cataract. Sixty-five （FAMILY-1） and sixty two （FAMILY-2） single-nucleotide polymorphisms and indels were selected by recommended filtering criteria.Segregation was then analyzed by applying Sanger sequencing with the family members. A heterozygous CRYBB1 mutation in exon 4 （c.347T〉C, p.L116P） was identified in sixteen patients in FAMILY-1. A heterozygous CRYBB2 mutation in exon 5 （c.355G〉A, p.G119R） was identified in three patients in FAMILY-2. Each mutation cosegregated with the affected individuals and did not exist in unaffected family members and 200 unrelated normal controls.The mutation was predicted to be highly conservative and to be deleterious by both PolyPhen-2 and SIFT.CONCLUSION：TheCRYBB1 mutation（c.347T〉C）and CRYBB2 mutation （c.355G〉A） are novel in patients with congenital cataract. We summarize the variable phenotypes among the patients, which expanded the phenotypic spectrum of congenital cataract in a different ethnic background.
文摘目的:研究beta-B2晶状体蛋白(CRYBB2)缺失对小鼠晶状体自噬的影响。方法:取6月龄野生型(WT)和Crybb2基因敲除型(Crybb2^KO)小鼠各6只,取晶状体组织,透射电子显微镜观察各组小鼠晶状体组织自噬的改变,用Western blot法检测两组小鼠自噬相关蛋白的相对表达量。结果:透射电子显微镜下观察发现,与WT小鼠相比,Crybb2KO小鼠晶状体核区线粒体累积明显,皮质区自噬小体数量增多。Western blot结果显示,Crybb2KO小鼠晶状体组织LC3B表达显著低于WT小鼠(0.09±0.01 vs 0.26±0.05),P62及p-mTOR表达(0.64±0.09和0.41±0.03)显著高于WT小鼠(0.43±0.07和0.27±0.02)。结论:CRYBB2晶状体蛋白缺失会影响晶状体自噬,其机制可能与mTOR信号通路的自噬相关,最终导致白内障产生。
基金This study was supported by grants for Natural Science Foundation of China(NSFC 81670835 and NSFC 81600719)the Shanghai Science and Technology Commission(11231200602)the Visual Impairment and Reconstruction Key Laboratory of Shanghai(12DZ2260500).
文摘Genetic alterations are a major cause of microphthalmos,while novel-related genes and mutations in microphthalmos have rarely been explored.To identify the underlying genetic defect responsible for microphthalmos eyes in two three-generation Chinese families,we screened 425 genes involved in common inherited non-syndromic eye diseases with next-generation sequencing-based target capture sequencing of the two probands of two three-generation Chinese families diagnosed with microphthalmos.Variants were filtered and analyzed to identify possible disease-causing variants before Sanger sequencing validation.We enrolled two families with microphthalmos(Family 1:microphthalmos with congenital ocular coloboma and Family 2:simple microphthalmos).Two novel heterozygous mutations,Peroxidasin(PXDN)c.3165C>T(p.Pro1055Pro)and PXDN c.2640C>G(p.Arg880Arg),were found in Family 1,and Crystallin Beta B2(CRYBB2)c.481G>A(p.Gly161Arg)was found in Family 2,but none of the mutations were found in the unaffected individuals,who were phenotypically nor-mal.Multiple orthologous sequence alignment(MSA)revealed that the CRYBB2 p.Gly161Arg mutation was a deleterious effect mutation.In conclusion,the three novel mutations found in our study extend our current understanding of the genetic basis of microphthalmos and provide early pre-symptomatic diagnosis and emphasize the significance of genetic diagnosis of microphthalmos.
文摘PURPOSE. To study some functional candidate genes in cataract families of Indi an descent. METHODS. Nine Indian families, clinically documented to have congeni tal/childhood cataracts, were screened for mutations in candidate genes such as CRYG (A→D), CRYBB2, and GJA8 by PCR analyses and sequencing. Genomic DNA sample s of either probands or any representative affected member of each family were P CR amplified and sequenced commercially. Documentation of single nucleotide poly morphisms (SNPs) and candidate mutations was done through BLAST SEARCH(http://ww w.ncbi.nlm.nih.gov/ blast/Blast.- cgi?). RESULTS. Several single nucleotide polymorphisms in CRYG, CRYBB2, and G JA8 genes were observed. Because they do not co-segregate with the phenotype, t hey were excluded as candidates for the cataract formation in these patients. However, a substitution (W151C in exon 6 of CRYBB2) was identi fied as the most likely causative mutation underlying the phenotype of central n uclear cataract in all affected members of family C176. Protein structural inter pretations demonstrated that no major structural alterations could be predicted and that even the hydrogen bonds to the neighboring Leu166 were unchanged. Surpr isingly, hydropathy analysis of the mutant βB2-crystallin featuring the amino acids at position 147 to 155, further increased the hydrophobicity, which might impair the solubility of the mutant protein. Finally, the Cys residue at positio n 151 might possibly be involved in intramolecular disulphide bridges with other cysteines during translation, possibly leading to dramatic structural changes. CONCLUSIONS. Exon 6 of CRYBB2 appears to be a critical region susceptible for mu tations leading to lens opacity.
