VPS13B gene variation and clinical phenotype of Cohen syndrome in a Chinese Han family / 中华实验眼科杂志

Objective:To analyze the pathogenicity and clinical characteristics of patients with Cohen syndrome caused by a compound heterozygous variation of VPS13B gene. Methods:A pedigree investigation was conducted.A Chinese Han family with Cohen syndrome was recruited from Henan Eye Hospital in September 2021.There were three members of two generations in this family, including one patient.The clinical data of the proband and his parents were collected, and the relevant ophthalmic and general examinations were performed to evaluate the clinical phenotype.The peripheral venous blood samples of the family members were collected to extract whole genomic DNA, and the whole exome sequencing was performed.Sanger sequencing and pedigree co-segregation analysis were performed among the family members.According to the ACMG guidelines, the pathogenicity of the selected variants was evaluated and the online tools were used to predict the pathogenicity of the variants.Relevant literature of Cohen syndrome were retrieved in Online Mendelian Inheritance in Man (OMIM) and PubMed, China National Knowledge Infrastructure and Wanfang databases by taking Cohen syndrome and VPS13B gene as the searching keywords.The clinical manifestations and pathogenic variants of patients in the literature were summarized, and the relationship between genotype and clinical phenotype was analyzed.This study protocol adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Henan Eye Hospital (No.HNEECKY-2019[15]). Both the subject and the patient's guardian were aware of the study purpose and method.Written informed consent was obtained. Results:The family was consistent with autosomal recessive inheritance.The proband, a 5-year-old male, had bilateral night blindness with photophobia, ptosis, lower eyelid entropion, and trichiasis; high myopia in both eyes; osteoblastoid pigmentation in the peripheral retina, atrophy and thinning of the outer layer of the peripheral retina, extinguished flashing electroretinogram; global growth retardation, typical facial features, slender fingers and toes, flatfoot, foot valgus, dystonia, no cardiac abnormalities; excessively cheerful personality.The clinical manifestations of the proband were consistent with Cohen syndrome.No obvious abnormality was found in the clinical phenotype and the auxiliary examination of the proband's parents.Whole exon sequencing revealed that the proband carried two heterozygous variations, a nonsense variation c. 11713C>T(p.Gln3905*) and a splicing variation c. 6940+ 1G>T.Sanger sequencing confirmed that the above variations were co-segregated in this family.c.11713C>T(p.Gln3905*) was a novel variant, which prematurely terminated the protein encoded by it and affected the normal function of the protein.The two variations were pathogenic variants according to the ACMG guidelines.A total of 12 articles on variants and clinical characteristics of Cohen syndrome in China were retrieved.Combined with the results of this study, a total of 24 VPS13B variants were found in Chinese patients, of which the incidence of frameshift variation was 41.7%(10/24), missense variation 20.8%(5/24), splicing variation 20.8%(5/24) and nonsense variation 16.7%(4/24), respectively.The onset age of patients with Cohen syndrome was from 28 days to 12 years old.The symptoms such as nerve system, eye, brain, and bone were sporadic, and the clinical manifestations were highly heterogeneous. Conclusions:A novel pathogenic variation c. 11713C>T is found in the VPS13B gene of the Cohen syndrome pedigree in this study, and expands the pathogenic variation spectrum of the VPS13B gene.The clinical manifestations of Cohen syndrome are highly heterogeneous.

Genotypes and phenotypes analysis of a novel complex heterozygous mutation of CEP290 related isolated cone-rod dystrophy / 中华眼底病杂志

Objective:The clinical phenotypes and pathogenicity of isolated cone-rod dystrophy (CORD) caused by two novel complex heterozygous variants of the CEP290 gene were analyzed using high-resolution multi-mode imaging and gene detection techniques. Methods:A retrospective study. Two patients and two family members from a CORD family who were diagnosed by genetic testing at Henan Provincial People's Hospital in December 2021 were included in the study. All subjects underwent best-corrected visual acuity (BCVA), color fundus photography, autofluorescence, swept-source optical coherence tomography (SS-OCT), adaptive optics fundus imaging, static threshold field, full field and multiple electroretinogram (ERG) examination, as well as other systemic examinations throughout the body. The peripheral venous blood of the subjects was collected, and the whole genome DNA was extracted. DNA sequencing was performed using the Inherited Retinal Disease Kit PS400, and Sanger verification and pedigree co-segregation analysis were performed on the suspected pathogenic mutation sites. Validation was performed by Sanger sequencing, pathogenicity analysis was performed in accordance with the American College of Medical Genetics and Genomics (ACMG) guidelines. Conservation of variation among different species was analyzed by GERP++, Clustal Omega and Weblogo.Results:Both patients were male, and their ages were 21 and 29 years old, respectively. The right eye and left eye about BCVAs were 0.7, 0.4 and 0.3, 0.4, respectively. The full field and multiple electroretinogram ERG showed a decreased function of cones and rods, especially cones. SS-OCT showed thinning of the outer nuclear layer of macular, and attenuation of ellipsoid zone reflectivity in B-scan. Adaptive optics fundus imaging examination showed that the arrangement of cone cells in the fovea of the fovea was disordered and the density decreased, and the retinal pigment epithelial cells were seen through the atrophy of cone cells in some areas at 10°visual angle. No obvious abnormality was found in other systemic examinations of the whole body. Genetic testing showed that 2 novel compound heterozygous variants c.950T >A (p.Leu317*) (M1) and c.4144_4149del (p.Tyr1382_Glu1383del) (M2) in CEP290 were found in two patients. The first variant was predicted to be harmful in MutationTaster and CADD. GERP++ showed highly conserved among different species. The pathogenicity of the variant was suspected to be likely pathogenic according to ACMG guidelines. The pathogenicity of the second variant was uncertain significance. The parents of the proband had no similar ocular abnormalities. Verified by Sanger sequencing, it was consistent with co-separation in the family. Conclusions:Patients with pure CORD caused by CEP290 gene mutation still retain better vision when the cone structure is abnormal, the density is decreased, and the function of cone and rod cells is decreased. CEP290 M1 and M2 are newly discovered nonsense mutations and newly discovered deletion mutations, which expanded the causative gene spectrum of pure CORD.

Novel compound heterozygous mutations in the PCDH15 gene in a family affected with Usher syndrome type 1F with retinitis pigmentosa sine pigmento / 中华眼底病杂志

Objective:To identify the causative gene in a family affected with Usher syndrome (USH) with retinitis pigmentosa sine pigmento (RPSP) and to analyze the genotype-phenotype correlation.Methods:A retrospective clinical study. A 9-year-old girl with RPSP type 1F USH diagnosed in the ophthalmology clinic of Henan Provincial People's Hospital in November 2019 and her parents were included in the study. The patient had bilateral night blindness for more than 4 years, she suffered from hearing loss 7 years, and is currently binaural sensorineural deafness. The best corrected visual acuity in both eyes was 0.5 +. There was showed no obvious pigmentation on the fundus. The visual acuity of the peripheral field of vision decreased. Optical coherence tomography showed that the outer layer of the peripheral retina became thinner and the ellipsoid band disappeared. On electroretinogram examination, the rod and cone system response was severely decreased. The clinical phenotype of the parents of the child were normal. The peripheral venous blood of the child and his parents were extracted, the whole genome DNA was extracted, the custom developed targeted capture kit (PS400) was used, and the next-generation sequencing technology was used to detect genetic mutations. The suspected pathogenic mutation sites were verified by Sanger; co-segregation was performed among family members. The pathogenicity of variants were evaluated according to the interpretation standards and guidelines of sequence variants. Bioinformatics techniques were used to assess the impact of variants on encoded proteins. Results:The results of genetic testing showed that the proband detected the PCDH15 gene c.4109dupA (p.K1370fs) (M1), c.17dupA (p.Y6_L7delinsX) (M2) compound heterozygous mutation sites, verified by Sanger sequencing, the mutations were in the family in a state of co-segregation. According to the evaluation of sequence variation interpretation standards and guidelines, M1 and M2 were pathogenic variants of the PCDH15 gene. M1 led to a complete change in the transmembrane structure of the encoded protein, and M2 caused the gene to only translate 6 amino acids, which predicted that the PCDH15 protein cannot be synthesized. According to the clinical phenotype, gene mutation pathogenicity and protein structure prediction, the final clinical diagnosis was PCDH15-related type 1F. Conclusions:PCDH15 genes c.4109dupA and c.17dupA are the pathogenic mutation sites of USH in this family. These compound heterozygous new mutations lead to the failure of normal synthesis of PCDH15 protein, which leads to ocular and ear manifestations.

Quality control analysis of brain tissue samples from Shanghai Brain Bank / 解剖学报

Objective To evaluate the feasibility of using brain tissues from Shanghai Brain Bank for the applications on biological research through the analysis of pH value of cerebrospinal fluids, RNA integrity number (RIN), transcriptome, proteome and morphology of brain tissues. Methods The pH value of fresh cerebrospinal fluid was detected by pH test paper; the RNA integrity of cryopreserved brain tissues was examined by Agilent RNA 6000 Nano chip and Agilent 2100 bioanalyzer; the transcriptome sequencing of superior temporal gyrus or caudate was performed using BGIseq-500 sequencer; the proteome of cryopreserved brain tissues was analyzed by Q Exactive HF mass spectrometer; at last, the morphology of the superior temporal gyrus was observed by HE staining. Results The pH value of the cerebrospinal fluid on average was about 6.5. The RIN values of more than 65% of brain tissues were more than 6, indicating good RNA quality. The clean reads ratio after transcriptome sequencing filtering was basically above 80%, indicating that the quality of sequencing library was high. The mass spectrometry analysis of frozen brain samples yielded more than 4000 protein groups and 30 000 peptides, indicating high quality of proteomic data. The morphology of brain tissues was relatively normal, with clearly visible neurons. Conclusion The quality of RNA and protein of brain tissues from Shanghai Brain Bank meets the basic needs for molecular and biological research, and the fixed brain samples can be used for morphological observations.

Analysis of USH2A gene mutation and clinical phenotype in families with Usher syndrome type 2 and retinitis pigmentosa / 中华眼底病杂志

Objective:To observe the gene mutations and clinical phenotypes in patients with Usher syndrome type 2 (USH2) and retinitis pigmentosa (RP).Methods:From August 2018 to January 2019, 4 patients and 11 normal family members from 3 families of USH2 and RP who visited Henan Eye Hospital were enrolled in the study. Detailed medical history was obtained and visual acuity, fundus color photography, OCT, visual field, full field ERG examination were performed. Among the three families, pedigree 1 was diagnosed with USH2, pedigree 2 and pedigree 3 were diagnosed with RP. The peripheral venous blood of patients and their family members were collected, and the whole genomic DNA was extracted. Targeted capture next generation sequencing analysis was performed on these members, and Sanger sequencing and family cosegregation were verified.Results:In the family F1, the proband had symptoms of RP and sensorineural deafness. Sequencing revealed two heterozygous frameshift variants: c.13877-13880 del AGAC (p. Q4626P) in exon 64 and c.798 del T (p. F266L) in exon 5 of USH2A. Both patients of family 2 and 3 showed RP signs without deafness. Two heterozygous variants c.15178T> C (p. S5060 P) in exon 70 and c.6986C> A (p. P2329H) in exon 37, and a pathogenic heterozygous variant c.5836C> T (p. R1946X) in exon 29 of USH2A were identified in family F2. A heterozygous missense variant c.14951C> T (p. P4984L) in exon 68 and a variant c.11156G> A (p. R3719H) in exon 57 of USH2A were found in family F3. The results of conservation analysis showed that the corresponding amino acid sites of USH2A p.Q4626P, p.F266L, p.S5060P, p.P2329H and p.P4984L were highly conserved in many species. Among these 7 pathogenic variants detected, M1-M4 and M6 were novel.Conclusions:Mutation USH2A gene are the main cause of USH2 and non-syndromic RP. Different variants affect protein translation and synthesis, consequently causing different clinical phenotypes.

X linked rod-cone dystrophy associated with a novel splicing variation in the intron of OPN1LW gene / 中华实验眼科杂志

Objective:Mutations in the OPN1LW gene located in X chromosome usually lead to blue cone monochromacy.Variations in OPN1LW gene usually occur in the exon region, but was rare in the intron region.This study was to report a Chinese family with X-linked rod-cone dystrophy associated with a novel OPN1LW gene hemizygotic splicing variation and analyze the clinical phenotype and gene mutation characteristics Methods:A pedigree investigation was performed.The family members clinically diagnosed as rod-cone dystrophy with myopia were enrolled in Henan Provincial People's Hospital on January 9, 2020.Detailed ophthalmological examination was carried out, and the periphery venous blood was collected for DNA extraction.The target gene sequencing panel PS400 developed by Henan Clinical Research Center for Eye Diseases and whole exon sequencing were used to detect pathogenic mutations.Sanger sequencing and pedigree co-segregation were used to verify variations.The pathogenicity of the novel variation was analyzed based on American College of Medical Genetics (ACMG) Guidelines and online tools SIFT, Polyphen2, Mutation Taster.This study adhered to the Declaration of Helsinki, and the study protocol was approved by the Medical Ethics Committee of Henan Eye Hospital (HNEECKY-2019 [15]). Written informed consent was obtained from each family member before any medical examination.Results:The proband was a 5-year-old boy with poor vision, red-green blindness and nystagmus in both eyes.No obvious abnormality in ocular anterior segment was found.The boundary of optic disc was clear and the color was reddish, and the reflection of macular fovea was clearly visible.OCT image showed indistinct reflection of some ellipsoids in macular area of both eyes.The amplitudes of a and b waves of full-field ERG were not recorded in scotopic 0.01 scale and significantly reduced in scotopic 3.0 and photopic 3.0 ERG.The uncle of the proband had a more severe clinical phenotype.Wide-angle fundus photography showed high myopia findings, peripheral retinal atrophy and sporadic black lesions, and autofluorescence examination showed attenuated fluorescence in peripheral retina.No obvious abnormality was found in the middle-peripheral retinal region.The results of two kinds next generation sequencing showed a novel hemizygotic splicing variation c. 112+ 2T>G in the intron of OPN1LW gene and an unreported heterozygous variation c. 1913A>C (p.Y638S) in the SEMA4A gene.The c. 112+ 2T>G mutation further leaded to the sequence change of classic splice donor of intron 1.According to the ACMG guidelines, the pathogenicity score was PVS1+ PM2+ PP1, which was considered as a pathogenic level. Conclusions:This is the first report of X-linked rod-cone dystrophy associated with OPN1LW gene variation, and this novel variant c. 112+ 2T>G locates in the intron region.This result is different from past knowledge that variations of OPN1LW gene primarily occur in exon.This study expands the mutational spectrum of OPN1LW gene inducing retinal degeneration and the spectrum of clinical phenotype.

Potential value of autoantibodies as biomarkers of chronic graft-versus-host disease after allogeneic stem cell transplantation / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

We investigated the value of autoantibodies as biomarkers of chronic graft-versus-host disease (cGVHD) by analyzing the autoantibody profiles of 65 patients (34 cGVHD and 31 non-cGVHD) surviving longer than three months after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Autoantibodies to at least one antigen were detected in 45 patients (70.8%), with multiple autoantibodies detected in 30 patients (46.2%). Antinuclear antibodies (ANAs) were the most frequently detected autoantibodies, with a significantly higher prevalence in non-cGVHD patients and cGVHD patients than that in healthy controls (HCs). ANA-nucleolar (ANA-N) was the main immunofluorescence pattern of ANA-positivity in both the non-cGVHD and cGVHD groups. There was a higher prevalence of anti-Ro52-positivity in non-cGVHD and cGVHD patients than in HC. Liver cGVHD was significantly associated with anti-Ro52-positivity. However, cGVHD activity and severity were not associated with the presence of autoantibodies. Similarly, there were no significant differences in overall survival or relapse among the four groups of patients expressing autoantibodies. Our results suggest that autoantibodies have limited value in predicting cGVHD.

Stereoselective glucuronidation of carvedilol by Chinese liver microsomes / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>To study the stereoselective glucuronidation of carvedilol (CARV) by three Chinese liver microsomes.</p><p><b>METHODS</b>The metabolites of CARV were identified by a hydrolysis reaction with beta-glucuronidase and HPLC-MS/MS. The enzyme kinetics for CARV enantiomers glucuronidation was determined by a reversed phase-high pressure liquid chromatography (RP-HPLC) assay using (S)-propafenone as internal standard after precolumn derivatization with 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosylisothiocyanate.</p><p><b>RESULTS</b>Two CARV glucuronides were found in three Chinese liver microsomes incubated with CARV. The non-linear regression analysis showed that the values of K(m) and V(max) for (S)-CARV and (R)-CARV enantiomers were (118+/-44) micromol/L, (2 500+/-833) pmol/(min.mg protein) and (24+/-7) micromol/L, (953+/-399) pmol/(min.mg protein), respectively.</p><p><b>CONCLUSION</b>These results suggested that there was a significant (P<0.05) stereoselective glucuronidation of CARV enantiomers in three Chinese liver microsomes, which might partly explain the enantioselective pharmacokinetics of CARV.</p>