OBJECTIVE: To explore the coincidence rate of G-banding karyotype analysis and fluorescence in situ hybridization (FISH) for the diagnosis of children with sex chromosome mosaicisms. METHODS: A retrospective analysis was carried out for 157 children with suspected sex chromosome abnormalities who had presented at Shenzhen Children's Hospital from April 2021 to May 2022. Interphase sex chromosome FISH and G-banding karyotyping results were collected. The coincidence rate of the two methods in children with sex chromosome mosaicisms was compared. RESULTS: The detection rates of G-banding karyotype analysis and FISH were 26.1% (41/157) and 22.9% (36/157) , respectively (P > 0.05). The results of G-banding karyotype analysis showed that 141 cases (89.8%) were in the sex chromosome homogeneity group, of which only 5 cases (3.5%) were inconsistent with the results of FISH. There were 16 cases (10.2%) in the sex chromosome mosaicism group, of which 11 cases (68.8%) were inconsistent with the results of FISH. There was a statistical difference between the two groups in the coincidence rate of the results of the two methods (P < 0.05). CONCLUSION No significant difference was found between G-banding karyotype analysis and FISH in the detection rate of chromosome abnormalities. The coincidence rate in the mosaicism group was lower than that in the homogeneity group, and the difference was statistically significant. The two methods should be combined for clinical diagnosis.
Humans ; Mosaicism ; In Situ Hybridization, Fluorescence/methods* ; Retrospective Studies ; Karyotyping ; Chromosome Aberrations ; Sex Chromosome Aberrations ; Karyotype ; Chromosome Banding ; Sex Chromosomes

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

OBJECTIVE: To define the nature and origin of a chromosomal aberration in a child with unexplained growth and development retardation, and to analyze its genotype-phenotype correlation. METHODS: A child who had presented at the Affiliated Children's Hospital of Zhengzhou University on July 9, 2019 was selected as the study subject. Chromosomal karyotypes of the child and her parents were determined with routine G-banding analysis. Their genomic DNA was also analyzed with single nucleotide polymorphism array (SNP array). RESULTS: Karyotyping analysis combined with SNP array suggested that the chromosomal karyotype of the child was 46,XX,dup(7)(q34q36.3), whilst no karyotypic abnormality was found in either of her parents. SNP array has identified a de novo 20.6 Mb duplication at 7q34q36.3 [arr[hg19] 7q34q36.3(138335828_158923941)×3] in the child. CONCLUSION The partial trisomy 7q carried by the child was rated as a de novo pathogenic variant. SNP array can clarify the nature and origin of chromosomal aberrations. Analysis of the correlation between genotype and phenotype can facilitate the clinical diagnosis and genetic counseling.
Female ; Humans ; Trisomy/genetics* ; Phenotype ; Genotype ; Karyotyping ; Chromosome Banding

OBJECTIVE: To diagnose and fine map a deletion in chromosome region 2q37. METHODS: G-banded chromosomal karyotyping, multiplex ligation-dependent probe amplification (MLPA), single nucleotide polymorphism array (SNP-array), and fluorescence in situ hybridization (FISH) were carried out in conjunct for the analysis. RESULTS: The patient was found to have karyotype of 46,XY,del(2)(q3?), MLPA revealed one copy number of both CAPN10-3 and ATG4B-7 genes from the 2q37.3 region, Both parents were found to be normal upon chromosome karyotyping and MLPA. SNP-array has found a 9.7 Mb deletion in the 2q37.1.37.3 region. FISH analysis has confirmed there is a single copy for 2q37.3. CONCLUSION Combination of MLPA, FISH and SNP-array have enabled accurate diagnosis for the patient, and also provided more clues for the correlation of genotype with the phenotype of the disease, and a basis for genetic counseling.
Chromosome Banding ; Chromosome Deletion ; Humans ; In Situ Hybridization, Fluorescence ; Karyotyping ; Phenotype

OBJECTIVE: To explore the genetic basis for a fetus with structural brain abnormalities. METHODS: The karyotypes of the fetus and its parents were analyzed by conventional G-banding. Chromosome microarray analysis (CMA) was carried out to detect chromosomal microdeletion and microduplication. RESULTS: No kartotypic abnormality was detected in the fetus and its parents. CMA has identified a 194 kb microduplication at Xq25 in the fetus, which encompassed exons 4-35 of the STAG2 gene and was derived from its mother. CONCLUSION The Xq25 duplication encompassing part of the STAG2 gene probably underlay the brain malformation in the fetus.
Chromosome Banding ; Female ; Fetus ; Genetic Testing ; Humans ; Karyotyping ; Pregnancy ; Prenatal Diagnosis

OBJECTIVE: To investigate the clinical phenotype and genetic diagnosis of an infant featuring multiple hair and hyperbilirubinemia. METHODS: Conventional G-banding analysis, chromosomal microarray analysis (CMA) and fluorescence in situ hybridization (FISH) for the patient were conducted, G-banding analyses of peripheral blood for the infant's parents were also performed. RESULTS: We investigated an infant who carries a unbalanced, maternally inherited karyotype 46, X, der (X) t (X;1) (p11.22; q21.3) in which CMA and FISH analyses disclosed a 1q21.3q44 duplication of 93.03 Mb and Xp22.33p11.22 deletion of 54.53 Mb. CONCLUSION The phenotypes of this infant can probably be attributed to the 1q21.3q44 duplication and Xp22.33p11.22 deletion, which were maternally inherited.
Chromosome Banding ; Chromosome Deletion ; Genetic Testing ; Humans ; In Situ Hybridization, Fluorescence ; Karyotyping ; Translocation, Genetic

OBJECTIVE: Utilize high-resolution chromosome analysis and microarray detection to determine the genetic etiology of infertility of a 32-year old female patient. METHODS: The peripheral blood of the patient was cultured for high-resolution chromosome G and C banding karyotype analysis, and then 750K SNP-Array chip detection was performed. RESULTS: Karyotype analysis results showed that the patient's karyotype was 45,XX,-13 [7]/46,XX,r(13) (p13q34) [185]/46,XX,dic r(13;13)(p13q34;p13q34) [14]/ 47,XX,+der(13;13;13;13) (p13q34;p13q34;p13q34; p13q34), dic r(13;13) [1]/ 46,XX [3]. The microarray results showed that the patient had a 3.3 Mb deletion in the 13q34 segment of chromosome 13, which may be related to infertility. CONCLUSION Infertility of the patient reported in this article may be related to the deletion of chromosome segment (13q34-qter).
Adult ; Chimera ; Chromosome Banding ; Chromosome Deletion ; Chromosome Disorders/genetics* ; Dacarbazine ; Female ; Humans ; Infertility/genetics* ; Ring Chromosomes

OBJECTIVE: To explore the genetic etiology of a child featuring global developmental and mental retardation. METHODS: Chromosome G-banding karyotype analysis, copy number variation sequencing (CNV-seq) and high-resolution chromosome banding were used to screen the genomic variant in the child and his parents. RESULTS: Both the child and his father were found to have a karyotype of 46,XY,del(18)(q21.1q21.3), whilst his mother was 46,XX. CNV-seq analysis showed that the child was arr[19]18q21.2-q21.32(chr18:48 422 190-58 039 582)×1, with a 10.58 Mb deletion which encompassed the TCF4 gene. The same deletion was found in neither parent. High-resolution banding revealed that the father has a fragment of 18q21.1q21.3 inserted into 5p13.1. CONCLUSION The child was diagnosed with Pitt-Hopkins syndrome due to the 18q21.2q21.32 deletion. Chromosome karyotyping and CNV-seq can effectively identify submicroscopic chromosome anomalies.
Child ; Chromosome Banding ; Chromosome Deletion ; DNA Copy Number Variations ; Facies ; Humans ; Hyperventilation ; Intellectual Disability/genetics*

OBJECTIVE: To explore the genetic etiology for a patient featuring intellectual disability and torticollis. METHODS: Peripheral blood sample was collected from the patient and subjected to G-banded karyotyping analysis and single nucleotide polymorphism array (SNP-array) assay. RESULTS: The patient was found to have a chromosomal karyotype of 46,XX. SNP-array revealed that she has harbored a 3.8 Mb microdeletion at 10q26.3 which has encompassed 21 OMIM genes including EBF3 and ECHS1, and a 7.3 Mb duplication at 18q22.3q23 which has encompassed 19 OMIM genes including TSHZ1 and TXNL4A. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the 10q26.3 deletion was predicted to be pathogenic, whilst the 18q22.3q23 duplication was predicted to be variation of unknown significance. CONCLUSION The clinical phenotype of the patient may be mainly attributed to the 10q26.3 microdeletion, and haploinsufficiency of the EBF3 gene may account for her intellectual deficiency. Above finding has provided a basis for genetic counseling for the patient.
Female ; Animals ; Genetic Testing ; Genetic Counseling ; Karyotyping ; Chromosome Banding ; Genomics

OBJECTIVE: To explore the genetic etiology for a newborn with corneal opacity. METHODS: The neonate and her parents were subjected to routine G-banding chromosomal karyotyping analysis. Copy number variation (CNV) was analyzed with low-coverage whole-genome sequencing (WGS) and single nucleotide polymorphism microarray (SNP array). RESULTS: No karyotypic abnormality was found in the newborn and her parents. Low-coverage WGS has identified a de novo 5.5 Mb microdeletion at chromosome 8q21.11-q21.13 in the neonate, which encompassed the ZFHX4 and PEX2 genes. The result was confirmed by SNP array-based CNV analysis. CONCLUSION The newborn was diagnosed with chromosome 8q21.11 deletion syndrome. ZFHX4 may be one of the key genes underlying this syndrome.
Chromosome Banding ; Chromosomes, Human, Pair 8/genetics* ; DNA Copy Number Variations ; Female ; Genetic Testing ; Homeodomain Proteins/genetics* ; Humans ; Infant, Newborn ; Karyotyping ; Monosomy/genetics* ; Peroxisomal Biogenesis Factor 2/genetics* ; Polymorphism, Single Nucleotide ; Transcription Factors/genetics*