A 7-year-old girl was admitted to the hospital with rapidly progressive vision loss. Since 1 year of age, she had exhibited developmental delay accompanied by visual impairment and neutropenia. Combined with genetic testing and molecular pathogenicity analysis, she was diagnosed with Cohen syndrome (CS) caused by compound heterozygous variants in VPS13B (c.6940+1G>T and c.2911C>T). The c.6940+1G>T variant resulted in exon 38 skipping, leading to a frameshift and premature termination. Reverse transcription quantitative polymerase chain reaction revealed significantly reduced VPS13B gene expression (P<0.05). Bioinformatic analysis suggested that both variants likely produce truncated proteins. This case highlights that integrating clinical features with molecular pathogenicity assessment (DNA, RNA, and protein analysis) can improve early diagnostic accuracy for CS.
Humans ; Female ; Child ; Vesicular Transport Proteins/genetics* ; Developmental Disabilities/etiology* ; Muscle Hypotonia/etiology* ; Myopia/etiology* ; Heterozygote ; Intellectual Disability/etiology* ; Microcephaly/etiology* ; Obesity/genetics* ; Growth Disorders/etiology* ; Retinal Degeneration/genetics* ; Psychomotor Disorders/genetics* ; Fingers/abnormalities*

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

Deletion and duplication of the -3.7-Mb region in 17p11.2 result in two reciprocal syndrome, Smith-Magenis syndrome and Potocki-Lupski syndrome. Smith-Magenis syndrome is a well-known developmental disorder. Potocki-Lupski syndrome has recently been recognized as a microduplication syndrome that is a reciprocal disease of Smith-Magenis syndrome. In this paper, we report on the clinical and cytogenetic features of two Korean patients with Smith-Magenis syndrome and Potocki-Lupski syndrome. Patient 1 (Smith-Magenis syndrome) was a 2.9-yr-old boy who showed mild dysmorphic features, aggressive behavioral problems, and developmental delay. Patient 2 (Potocki-Lupski syndrome), a 17-yr-old boy, had only intellectual disabilities and language developmental delay. We used array comparative genomic hybridization (array CGH) and found a 2.6 Mb-sized deletion and a reciprocal 2.1 Mb-sized duplication involving the 17p11.2. These regions overlapped in a 2.1 Mb size containing 11 common genes, including RAI1 and SREBF.
Adolescent ; Asian Continental Ancestry Group/*genetics ; Child, Preschool ; *Chromosomes, Human, Pair 17 ; Comparative Genomic Hybridization ; Developmental Disabilities/etiology/genetics ; Gene Deletion ; Gene Duplication ; Humans ; Intellectual Disability/etiology/genetics ; Karyotyping ; Male ; Smith-Magenis Syndrome/diagnosis/*genetics ; Sterol Regulatory Element Binding Protein 1/genetics ; Transcription Factors/genetics

Developmental Disabilities ; diagnosis ; etiology ; genetics ; Humans ; Nervous System Malformations ; diagnosis ; etiology ; genetics

Albinism, Oculocutaneous ; complications ; diagnosis ; genetics ; Angelman Syndrome ; complications ; diagnosis ; genetics ; Child ; Chromosomes, Human, Pair 15 ; Developmental Disabilities ; etiology ; genetics ; Epilepsy ; etiology ; genetics ; Female ; Humans ; Intellectual Disability ; etiology ; genetics ; Karyotyping