OBJECTIVE: To investigate the clinical phenotype and genetic characteristics of a Chinese pedigree affected with Cohen syndrome. METHODS: A proband who was admitted to Zhengzhou People's Hospital on June 2, 2021 due to intellectual disability and developmental delay, in addition with her younger sister and other family members, were selected as the study subjects. Clinical data of the proband and her younger sister were collected. Genomic DNA was extracted from peripheral venous blood and chorionic villi samples. Chromosomal abnormalities were detected with chromosomal microarray analysis (CMA). Whole exome sequencing (WES) and Sanger sequencing were carried out to detect candidate variants in the proband. With RNA extracted from the peripheral blood samples, VPS13B gene transcripts and expression were analyzed by PCR and real-time quantitative PCR. Prenatal diagnosis was carried out at 12 weeks' gestation. RESULTS: The proband was a 10-year-old female with clinical manifestations including development delay, obesity, severe myopia and peculiar facial features. Her sister was 3 years old with a similar phenotype. CMA revealed no chromosomal abnormality in the proband, while WES results revealed that the proband and her sister had both harbored compound heterozygous variants of the VPS13B gene, namely c.10076_10077delCA (p.T3359fs*29) and c.6940+1G>T, which were respectively inherited from their mother and father. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), both variants were classified as pathogenic (PVS1+PS4+PM4+PP1; PVS1+PM2_Supporting+PM3+PP1). In vivo splicing assay confirmed that the c.6940+1G>T variant has produced a frameshift transcript with skipping of exon 38. Compared with the control group, the expression of RNA in the peripheral blood of the proband's parents has decreased to 65% ~ 70% (P < 0.01), whilst that in the proband and her sister has decreased to 40% (P < 0.001). Prenatal diagnosis at 12 weeks of gestation has found that the fetus only harbored the heterozygous c.10076_ 10077delCA variant. CONCLUSION The c.10076_10077delCA (p.T3359fs*29) frameshift variant and c.6940+1G>T splicing variant probably underlay the Cohen syndrome in this pedigree. Genetic testing has facilitated the diagnosis of this disease.
Female ; Humans ; East Asian People ; Intellectual Disability/genetics* ; Mutation ; Myopia/genetics* ; Pedigree ; Vesicular Transport Proteins/genetics* ; Child, Preschool ; Child

OBJECTIVE: To analyze genetic variant in a pedigree affected with congenital high myopia. METHODS: Whole exome sequencing (WES) was carried out for the proband. Suspected variation was verified with Sanger sequencing. The pedigree was also subjected to co-segregation analysis. RESULTS: WES has identified a novel splice site heterozygous variant (c.2556+1G>A) in the COL11A1 gene in the proband. Co-segregation analysis of the pedigree showed that the affected mother and two daughters of the proband have carried the same variant(c.2556+1G>A), while his unaffected father and sister did not. Based on the ACMG Standards and Guidelines for the Interpretation of Sequence Variants, the variant was classified as "likely pathogenic" (PVS1+PM2). CONCLUSION A novel splice variant (c.2556+1G>A) of the COL11A1 gene has been identified in a pedigree affected with congenital high myopia, which probably underlies the disease.
Collagen Type XI ; genetics ; Genetic Testing ; Heterozygote ; Humans ; Myopia ; genetics ; Pedigree ; Whole Exome Sequencing

A boy was admitted at the age of 17 months. He had psychomotor retardation in early infancy. Physical examination revealed microcephalus, unusual facies, and a single palmar crease on his right hand, as well as muscle hypotonia in the extremities and hyperextension of the bilateral shoulder and hip joints. Genetic detection identified two pathogenic compound heterozygous mutations, c.8868-1G>A (splicing) and c.11624_11625del (p.V3875Afs*10), in the VPS13B gene, and thus the boy was diagnosed with Cohen syndrome. Cohen syndrome is a rare autosomal recessive disorder caused by the VPS13B gene mutations and has complex clinical manifestations. Its clinical features include microcephalus, unusual facies, neutropenia, and joint hyperextension. VPS13B gene detection helps to make a confirmed diagnosis.
Base Sequence ; Developmental Disabilities ; diagnosis ; genetics ; Fingers ; abnormalities ; Humans ; Infant ; Intellectual Disability ; diagnosis ; genetics ; Male ; Microcephaly ; diagnosis ; genetics ; Muscle Hypotonia ; diagnosis ; genetics ; Mutation ; Myopia ; diagnosis ; genetics ; Neutropenia ; complications ; genetics ; psychology ; Obesity ; diagnosis ; genetics ; Psychomotor Disorders ; diagnosis ; etiology ; genetics ; Retinal Degeneration ; diagnosis ; genetics ; Vesicular Transport Proteins ; genetics

OBJECTIVETo analyze the mutation of COL9A2 gene and investigate the molecular pathogenesis of pathological myopia in a Han Chinese population.

METHODSMutation in the coding region of the COL9A2 gene was screened by Sanger sequencing in 200 subjects with pathological myopia and 200 normal controls. The detected variants were genotyped by SNaPshot method in another 200 myopic cases and 200 normal controls.

RESULTSSanger sequencing has failed to detect the reported D281fs frameshift mutation in the 200 cases. A novel variant, c.143G>C heterozygous missense mutation in exon 2, was identified in a myopic subject, and another novel variant, c.884G>A heterozygous missense mutation in exon 17, was found in another case. Neither was found in normal controls. One SNP (rs2228564) was detected in the coding region of the COL9A2 gene, but there was no significant difference in its allelic frequencies between the two groups (P> 0.05). Genotyping of the remainder 200 cases and 200 controls by SNaPshot method has found a c.143G>C in 1 case and c.884G>A in 2 cases, though no significant difference between the two groups was detected (P> 0.05).

CONCLUSIONThe D281fs frameshift mutation in the COL9A2 gene is not associated with pathological myopia in the studied Han Chinese population. Two novel mutations, c.143G>C in exon 2 and c.884G>A in exon 17 of the COL9A2 gene, may contribute to the development of pathological myopia.

Asian Continental Ancestry Group ; genetics ; China ; ethnology ; Collagen Type IX ; genetics ; Frameshift Mutation ; Humans ; Myopia, Degenerative ; genetics ; Sequence Analysis, DNA

BACKGROUNDDevelopment of myopia among young children is often contributed to the refractive status of the parents. This study was conducted to determine whether myopia can be inherited across the generation among a sample in the Klang Valley. Three generations involved are: G1 (grandparents), G2 (parents) and G3 (children).

METHODSSixty-two families were screened and forty families were selected to participate in this study. The inclusion criterion is having at least one myopic member in any of the three generations. Subjects (G2) were first asked to fill up a questionnaire form before their refractive status was determined by clinical examination that provided acuity of 6/6 or better. Refractive status of G1 was determined using information from the questionnaire while for G2 and G3 through clinical examination.

RESULTSGenerally, the prevalence of myopia is seen to increase throughout the generations from G1 being the lowest (25.6%) to G3 being the highest (41.1%). Strong genetic influence can be found between G1 and G2 as majority of myopes in G2 is when both parents were myopic. However, although the prevalence of myopia increased from G2 to G3, there was no strong genetical influence. Majority of subjects in G3 were non-myopes when both their parents were myopic.

CONCLUSIONParental history accounts for a limited proportion of variance in myopia development.

Adolescent ; Adult ; Aged ; Family Health ; Female ; Humans ; Malaysia ; epidemiology ; Male ; Middle Aged ; Myopia ; epidemiology ; genetics ; Retrospective Studies ; Surveys and Questionnaires ; Young Adult

OBJECTIVETo detect genetic mutations associated with autosomal dominant congenital stationary night blindness (ADCSNB) in a family from Henan province.

METHODSGenomic DNA was extracted from peripheral blood samples of 14 family members. Based on 3 genes reported previously, PCR primers were designed and corresponding exons containing the mutation sites were amplified with PCR. PCR products were purified and directly sequenced.

RESULTSA c.281C>T heterozygous missense mutation was detected in RHO gene in all of the patients. This mutation can cause a change of the protein structure (p.Thr94Ile). The same mutation was not detected in normal individuals from the family and 50 normal controls.

CONCLUSIONA c.281C>T mutation in RHO gene is responsible for the onset of ADCSNB in this Chinese family and results in symptoms of night blindness.

Adult ; Amino Acid Sequence ; China ; DNA Mutational Analysis ; methods ; Eye Diseases, Hereditary ; Female ; Genetic Diseases, X-Linked ; Genetic Predisposition to Disease ; Humans ; Male ; Molecular Sequence Data ; Mutation, Missense ; Myopia ; genetics ; Night Blindness ; genetics ; Rhodopsin ; genetics ; Sequence Alignment ; methods

We report a case of one sister and brother with mirror image myopic anisometropia. One sister and brother complained visual disturbance. The sister was 10 years 11 months old, and brother was 8 years 4 months old. Full ophthalmic examinations were performed, including slit lamp examination, intraocular pressure, keratometry, anterior chamber depth, axial length, fundus examination and the cycloplegic refraction. The cycloplegic refractive power was -15.50 dpt cyl.+4.50 dpt Ax 85degrees (right eye), -1.00 dpt cyl.+0.50 dpt Ax 90degrees (left eye) in the sister; -1.75 dpt cyl.+2.25 dpt Ax 90degrees (right eye), -9.50 dpt cyl.+4.00 dpt Ax 80degrees (left eye) in the brother. The co-occurrence of severe myopic anisometropia in a sister and brother is extremely rare. The present case suggests that severe myopic anisometropia may be related by genetic inheritance.
Anisometropia/*etiology/*genetics/physiopathology/therapy ; Child ; Female ; Humans ; Male ; Myopia/*complications/*genetics/physiopathology/therapy ; Refraction, Ocular ; *Siblings ; Visual Acuity

OBJECTIVETo map the candidate gene by linkage analysis in a Chinese family with autosomal dominant congenital retinaochoroidal coloboma.

METHODSA detailed clinical examination was performed for all patients in the family. The genomic DNA of all family members was extracted from peripheral blood leukocytes. Linkage analysis and genome-wide linkage screening was conducted using fluorescent detection of 398 microsatellite markers representing all autosomes at an average resolution of approximately 10 cM. Polymerase chain reaction was carried out to amplify all 398 microsatellite markers. The allele sizes were determined on ABI 3130-Avant genetic analyzer according to an internal size standard, and the results were analyzed using Genescan 3.1 and Genotyper 2.0 software.

RESULTSLinkage analysis showed the markers D2S2382-D2S301-D2S2244-D2S163 co-segregated with the disease locus in all affected members. The maximum Lod score was 3.01(D2S2382).

CONCLUSIONThe candidate region of the disease gene in the family was located in 2q34-2q35.

Asian Continental Ancestry Group ; Chromosome Mapping ; Coloboma ; genetics ; DNA Mutational Analysis ; Family ; Female ; Genetic Linkage ; Genotype ; Humans ; Lod Score ; Loss of Heterozygosity ; Male ; Microsatellite Repeats ; genetics ; Myopia ; genetics ; Pedigree ; Polymerase Chain Reaction

Myopia is an important cause of blindness, in which an image is focused in front of the retina. Genetic factors have been implicated in the pathogenesis of myopia. Based on the molecular genetic study, some genetic loci linked to myopia have been mapped, but no disease-causing gene has been identified. Here authors review the genetic study on myopia, including gene mapping and candidate gene screening.
Animals ; Chromosome Mapping ; Chromosomes, Human ; genetics ; Genetic Testing ; Humans ; Myopia ; genetics

OBJECTIVETo map the high myopia gene in a Chinese family with autosomal dominant high myopia.

METHODSA family with autosomal dominant high myopia in three generations was collected. Eighteen short-tandem-repeat markers on previously reported loci linked to high myopia were chosen for genotyping and two-point linkage analysis was carried out.

RESULTSThe spherical equivalent of affected individuals ranges from -6.00D to -20.00D and the genetic pattern is autosomal dominant. The LOD score was less than -1 in all 18 microsatellite markers, indicating that there was no linkage between these markers and the high myopia related genes in this family.

CONCLUSIONA novel myopia locus for high-grade myopia may exist in the kindred. Genome-wide scan will be needed to determine this novel locus.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Female ; Genetic Linkage ; Humans ; Lod Score ; Male ; Microsatellite Repeats ; genetics ; Middle Aged ; Myopia ; genetics ; Pedigree ; Polymorphism, Single Nucleotide ; Refraction, Ocular ; physiology ; Young Adult