OBJECTIVE: To explore the clinical characteristics and genetic basis of two brothers featuring X-linked alpha thalassemia mental retardation (ATR-X) syndrome. METHODS: An infant who had presented at the Qilu Children's Hospital in 2020 for unstable upright head and inability to roll over and his family were selected as the study subjects. The clinical features of the child and one of his brothers were summarized, and their genomic DNA was subjected to targeted capture and next generation sequencing (NGS). RESULTS: The brothers had presented with mental retardation and facial dysmorphisms. NGS revealed that they had both harbored a hemizygous c.5275C>A variant of the ATRX gene located on the X chromosome, which was inherited from their mother. CONCLUSION The siblings were diagnosed with ATR-X syndrome. The discovery of the c.5275C>A variant has enriched the mutational spectrum of the ATRX gene.
Humans ; Infant ; Male ; alpha-Thalassemia/diagnosis* ; Ataxia Telangiectasia Mutated Proteins/genetics* ; East Asian People ; Intellectual Disability/genetics* ; Mental Retardation, X-Linked/diagnosis* ; Pedigree ; X-linked Nuclear Protein/genetics*

OBJECTIVE: To explore the genetic etiology for a child featuring mental retardation, language delay and autism. METHODS: G-banding chromosomal karyotyping and single nucleotide polymorphism array (SNP-array) were carried out for the child and her parents. RESULTS: The child was found to have a 46,XX,dup(8p?) karyotype, for which both of her parents were normal. SNP-array revealed that the child has harbored a 6.8 Mb deletion in 8p23.3p23.1 and a 21.8 Mb duplication in 8p23.1p12, both of which were verified as de novo pathogenic copy number variants. CONCLUSION The clinical features of the child may be attributed to the 8p deletion and duplication. SNP-array can facilitate genetic diagnosis for children featuring mental retardation in conjunct with other developmental anomalies.
Humans ; Child ; Pregnancy ; Female ; Intellectual Disability/genetics* ; Prenatal Diagnosis ; Karyotyping ; Chromosome Banding ; Chromosome Deletion

OBJECTIVES: To summarize the clinical phenotype and genetic characteristics of children with autosomal dominant mental retardation type 5 caused by SYNGAP1 gene mutations. METHODS: A retrospective analysis was performed on the medical data of 8 children with autosomal dominant mental retardation type 5 caused by SYNGAP1 gene mutations who were diagnosed and treated in the Department of Pediatrics, Xiangya Hospital of Central South University. RESULTS: The mean age of onset was 9 months for the 8 children. All children had moderate-to-severe developmental delay (especially delayed language development), among whom 7 children also had seizures. Among these 8 children, 7 had novel heterozygous mutations (3 with frameshift mutations, 2 with nonsense mutations, and 2 with missense mutations) and 1 had 6p21.3 microdeletion. According to the literature review, there were 48 Chinese children with mental retardation caused by SYNGAP1 gene mutations (including the children in this study), among whom 40 had seizures, and the mean age of onset of seizures was 31.4 months. Frameshift mutations (15/48, 31%) and nonsense mutations (19/48, 40%) were relatively common in these children. In terms of treatment, among the 33 children with a history of epileptic medication, 28 (28/33, 85%) showed response to valproic acid antiepileptic treatment and 16 (16/33, 48%) achieved complete seizure control after valproic acid monotherapy or combined therapy. CONCLUSIONS Children with autosomal dominant mental retardation type 5 caused by SYNGAP1 gene mutations tend to have an early age of onset, and most of them are accompanied by seizures. These children mainly have frameshift and nonsense mutations. Valproic acid is effective for the treatment of seizures in most children.
Child ; Humans ; Intellectual Disability/diagnosis* ; Codon, Nonsense ; Retrospective Studies ; Valproic Acid ; ras GTPase-Activating Proteins/genetics* ; Mutation ; Seizures/genetics*

OBJECTIVE: To explore the clinical features and genetic basis for a child with Bainbridge-Ropers syndrome (BRPS). METHODS: Clinical data of the child were retrospectively analyzed. Copy number variation sequencing (CNV-seq) and trio based whole exome sequencing (trio-WES) were carried out. Prenatal diagnosis was provided for a at risk fetus from the pedigree, and genotype phenotype correlation was summarized through a literature review. RESULTS: The proband, a 6-year-old boy, has presented with feeding difficulties, specific craniofacial features, global developmental delay and intellectual disability, which has not improved after rehabilitation treatment. CNV-seq analysis of the patient showed no obvious abnormalities. A de novo heterozygous truncating variation, c.1448dupT (p.T484Nfs*5), was identified in the ASXL3 gene by trio-WES, which was a previously reported pathogenic variant. So far 14 Chinese patients with BRPS and ASXL3 variants have been reported. All patients have shown specific craniofacial features and delayed motor and speech development, and harbored 12 loss of function ASXL3 variants, which were de novo in origin and have clustered in exons 11 and 12 of the ASXL3 gene. CONCLUSION The heterozygous frameshift c.1448dupT (p.T484Nfs*5) variant of the ASXL3 gene probably underlay the disorder in this patient. BRPS should be considered in infants with feeding difficulties, special craniofacial features, global developmental delay and hand anomalies, and WES can help to delineate the pathogenesis and establish the definite diagnosis.
Child ; Humans ; Female ; Pregnancy ; Developmental Disabilities/genetics* ; Phenotype ; Pedigree ; DNA Copy Number Variations ; Retrospective Studies ; Transcription Factors/genetics* ; Syndrome ; Intellectual Disability/genetics* ; Prenatal Diagnosis ; China

OBJECTIVE: To analyze the (CGG)n repeats of FMR1 gene among patients with unexplained mental retardation. METHODS: For 201 patients with unexplained mental retardation, the (CGG)n repeats of the FMR1 gene were analyzed by PCR and FragilEase RESULTS: For the 201 patients with unexplained mental retardation, 15 were identified with full mutations of the FMR1 gene. The prevalence of fragile X syndrome (FXS) in patients with unexplained mental retardation was determined as 7.5% (15/201). Prenatal diagnosis was provided for 6 pregnant women with pre- or full mutations. Analysis revealed that women with mental retardation and full FMR1 mutations exhibited a skewed XCI pattern with primary expression of the X chromosome carrying the mutant allele. CONCLUSION FXS has a high incidence among patients with unexplained mental retardation. Analysis of FMR1 gene (CGG)n repeats in patients with unexplained mental retardation can facilitate genetic counseling and prenatal diagnosis for their families. FMR1 gene (CGG)n repeats screening should be recommended for patients with unexplained mental retardation.
Female ; Fragile X Mental Retardation Protein/genetics* ; Fragile X Syndrome/genetics* ; Humans ; Intellectual Disability/genetics* ; Mutation ; Pregnancy ; Prenatal Diagnosis

OBJECTIVE: To assess the clinical application of single nucleotide polymorphism microarray (SNP array) in patients with intellectual disability/developmental delay(ID/DD). METHODS: SNP array was performed to detect genome-wide DNA copy number variants (CNVs) for 145 patients with ID/DD in Women's Hospital, Zhejiang University School of Medicine from January 2013 to June 2018. The CNVs were analyzed by CHAS software and related databases. RESULTS: Among 145 patients, pathogenic chromosomal abnormalities were detected in 32 cases, including 26 cases of pathogenic CNVs and 6 cases of likely pathogenic CNVs. Meanwhile, 18 cases of uncertain clinical significance and 14 cases of likely benign were identified, no significant abnormalities were found in 81 cases (including benign). CONCLUSIONS SNP array is effective for detecting chromosomal abnormalities in patients with ID/DD with high efficiency and resolution.
Chromosome Aberrations ; DNA Copy Number Variations ; Genome-Wide Association Study ; Humans ; Intellectual Disability ; diagnosis ; genetics ; Oligonucleotide Array Sequence Analysis ; standards ; Polymorphism, Single Nucleotide

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 carry out genetic analysis for a fetus with Dandy-Walker malformation and provide prenatal diagnosis for its parents during the subsequent pregnancy.

METHODSRoutine G-banding was carried out to analyze the karyotype of the fetus and its parents, and next-generation sequencing (NGS) and fluorescence in situ hybridization (FISH) were used to verify the result.

RESULTSThe father showed a normal karyotype, while the mother was found to carry a balanced t(11; 22) (q23; q11) translocation. NGS and FISH analysis verified that the supernumerary marker chromosome carried by the fetus was der(22) t(11; 22) (q23;q11). The fetus was diagnosed with Emanuel syndrome. During the next pregnancy, the fetus was found to carry the same balanced translocation as its mother. After genetic counseling, the couple decided to continue with the pregnancy, and eventually delivered a healthy baby.

CONCLUSIONA fetal case of Emanuel syndrome has been identified. The derivative der(22) t(11; 22)(q23; q11) chromosome probably underlies the Dandy-Walker malformation in the fetus. Combined cytogenetic and molecular analyses can attain a more precise diagnosis for fetal abnormalities detected by ultrasonography.

Adult ; Chromosome Disorders ; diagnosis ; genetics ; Chromosomes, Human, Pair 11 ; Chromosomes, Human, Pair 22 ; Cleft Palate ; diagnosis ; genetics ; Female ; Follow-Up Studies ; Heart Defects, Congenital ; diagnosis ; genetics ; Humans ; Intellectual Disability ; diagnosis ; genetics ; Muscle Hypotonia ; diagnosis ; genetics ; Pregnancy ; Prenatal Diagnosis ; Translocation, Genetic

OBJECTIVETo provide genetic analysis for a pregnant woman with chromosomal translocations and intellectual disability, and to provide prenatal diagnosis for her fetus.

METHODSRoutine G-banding was performed to analyze the karyotypes of the woman and her fetus. Copy number variants were determined with array comparative genomic hybridization (array-CGH).

RESULTSThe pregnant woman has carried an apparently balanced translocation involving chromosomes 1, 2, 6 and 7, with a karyotype of 46, XX, t(1;2) (p22;p23), t(6;7) (q21;p15). The karyotype of her fetus was ascertained as 46, XY, t(6;7) (q21;p15) mat. Array-CGH has detected a 4 Mb microdeletion at 6q22.1-q22.31 (115 311 507-119 332 956) in both individuals. As the 6q22.1-q22.31 microdeletion may be associated with the main clinical manifestations of the woman, the family decided to terminate the pregnancy. The fetus was male and appeared to have no obvious abnormality.

CONCLUSIONPrenatal diagnosis for pregnant women with translocations and mental retardation is a challenging task. Combined application of cytogenetic analysis and array-CGH may facilitate the diagnosis and genetic counseling.

Adult ; Female ; Fetus ; abnormalities ; Genetic Testing ; methods ; Humans ; Intellectual Disability ; genetics ; Male ; Pregnancy ; Prenatal Diagnosis ; methods ; Translocation, Genetic ; genetics ; Young Adult

No abstract available.
Child, Preschool ; Chromosome Disorders/diagnosis/*genetics ; *Chromosomes, Human, Pair 8/genetics ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Intellectual Disability ; Karyotyping ; Mexico ; Oligonucleotide Array Sequence Analysis