Genetic analysis of a Chinese pedigree with Cohen syndrome due to compound heterozygous variants of VPS13B gene / 中华医学遗传学杂志

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.

Incidence of myopia in school going children in Rahim Yar Khan

Myopia is becoming a major health problem all over the world. To assess the incidence of myopia among school children and to determine the association of genetics, nutrition and close work to myopia. Prospective study. In Rahim Yar Khan district. Period: From Feb 2006 to June 2006. We conducted a cross sectional survey among school children of 8-15 years age. There was 300 children in this study from two school. They were checked for visual acquity and nutritional status after taking a complete personal and family history. Any student detected to have myopia was then brought to eye outdoor for further specialized check up and evaluation. A total 57 students [19%] were found to have myopia in school going children in Rahim yar Khan between ages 10-15 years. The genetic factor was present in 91% of myopes [P<0.001]. The average amount of near work after school in myopes was considerably more than the emmetropes P<0.05 for study and P<0.005 for recreational books. Regarding nutritional status, 30% myopes were mainourished whereas similar percentage of emmetropes was malnourished. In our study heredity was closely associated with myopia. The children in both groups [the myopes and emmetropes] did almost equal amount of near work for their studies but myopes spent more time in reading for pleasure than emmetropes who took more pleasure in out door sports activities. The nutritional status of children was not associated with incidence of myopia in our study

Avaliação genética e oftalmológica de pacientes com síndrome de Stickler tipo II / Genetic and ophthalmological assessment of patients with type II Stickler syndrome

OBJETIVOS: Diagnosticar, avaliar e descrever os achados clínico-genéticos e oftalmológicos de pacientes com síndrome de Stickler tipo II de uma mesma família. MÉTODOS: Todos os pacientes com alterações oftalmológicas foram submetidos à radiografia de mãos e punhos para idade óssea e posteriormente analisados pelo exame clínico-genético. O diagnóstico de síndrome de Stickler foi dado mediante análise clínica e correlação com o perfil metacarpofalangeano visualizado na radiografia. RESULTADOS: Síndrome de Stickler tipo II foi comprovada em 11 pacientes. Os achados oculares mais importantes foram: alta miopia (80 por cento), subluxação do cristalino (70 por cento), exotropia (50 por cento) e anomalias vítreo-retinianas (80 por cento) incluindo vazio vítreo (50 por cento). O exame clínico-genético revelou que 30 por cento dos pacientes apresentavam micrognatia, 50 por cento hipoacusia, 40 por cento depressão nasal e 60 por cento palato alto. Hipermotilidade articular e dedos longos foram demonstrados em 7 casos (70 por cento) e artropatia esteve presente em 3 pacientes (30 por cento dos casos). CONCLUSÕES: O diagnóstico da síndrome de Stickler é difícil devido à variabilidade fenotípica e a existência de outras síndromes genéticas com características semelhantes. As radiografias de mão e punho são de particular importância no diagnóstico desta síndrome.

PURPOSE: To diagnose, evaluate and describe the clinical, genetic and ophthalmic characteristics of a family with type II Stickler syndrome. METHODS: X-rays for bone age, clinical and genetic evaluation were performed in all patients with ocular alterations. The Stickler syndrome diagnosis was established after correlating these examinations. RESULTS: Type II Stickler syndrome was found in 11 patients. The most important ocular findings were: high myopia (80 percent), lens subluxation (70 percent), exotropia (50 percent) and vitreoretinal abnormalities (80 percent) including vitreous cavity (50 percent). The clinical genetic examination disclosed that 30 percent of the patients had micrognathia, 50 percent hearing loss, 40 percent nasal depression and 60 percent high palate. Seven cases had articular hypermotility and long fingers and arthropathy was present in 3 cases. CONCLUSION: Diagnosis of the Stickler syndrome is difficult due to its phenotypic variability and the existence of other genetic syndromes with similar characteristics. Hand and wrist radiographs are of particular importance in the diagnosis of this syndrome.

Polidactilia pós-axial e miopia progressiva / Postaxial polydactyly and progressive myopia

O presente trabalho apresenta três casos de associaçäo de miopia progressiva com polidactilia pós-axial, sendo que dois säo irmäos do sexo masculino, filhos de casal näo consanguíneo e o terceiro caso é de uma menina filha de pais consanguíneos. Verificou-se na literatura apenas um relato, de Czeizel e Brooser, em 1986, em que é descrita a mesma associaçäo de defeitos, transmitindo-se em quatro geraçöes de forma autossômica dominante. Acreditamos que nossos pacientes apresentam a mesma síndrome, porém nestas duas famílias existem indícios de que a transmissäo ocorra de forma autossômica recessiva.

Genetics of epidermal ridges: a study in subjects with refractive errors.

The dermatoglyphic characteristics of subjects with refractive errors when compared with control group revealed significant differences in both qualitative and quantitative parameters. The loops were increased in male myopics; the whorls were increased in male hypermetropics and astigmatics and the arches were decreased in all types of refractive errors in males. However, the whorls were decreased in female hypermetropics only. The mean total ridge count was significantly higher in male astigmatics only. As regards pattern intensity (fingers) no significant difference in the mean value was observed in either sex with any type of refractive errors when compared with those of controls.