OBJECTIVE: To explore the mechanism for the occurrence and phenotypic characteristics of Turner syndrome based on a prenatally diagnosed case of a mosaic karyotype containing double pseudo-isodicentric X chromosome and a review of relevant literature. METHODS: A fetus diagnosed with increased risk for trisomy 21 at the Provincial Hospital Affiliated to Shandong First Medical University in August 2023 was selected as the study subject. Clinical data of the fetus was collected. Following amniocentesis, chromosomal G-banding karyotype analysis and chromosomal microarray analysis (CMA) were carried out. This study has been approved by the Ethics Committee of the Hospital (Ethics No.: SWYX No. 2022-287). RESULTS: The early-trimester screening suggested a high risk of trisomy 21 (1/19), with free β-hCG of 116 ng/mL (MoM value 2.35), PAPP-A of 0.394 ng/mL (MoM value 0.12), and NT value of 1.3 mm, though no abnormality was found in the fetus at 19 weeks gestation. The karyotype of amniocyte was determined as 46,X,psu idic(X)(p11.21)[55]/45,X[27]/47,X,psu idic(X)(p11.21)×2[5]/46,XX[13]. CMA has yielded a result of arr[GRCh37] Xp22.33p11.21(168552_55585678)×1[0.67],Xp11.21q28(55703291_155233098)×3[0.5]. CONCLUSION Karyotypes of Turner syndrome are complex and diverse, and a rare 46,X,psu idic(X)(p11.21)[55]/45,X[27]/47,X,psu idic(X)(p11.21)×2[5]/46,XX[13] mosaic karyotype with double pseudo-isodicentric X chromosome has been identified. Literature review suggested that this karyotype may lead to phenotypic diversification and a risk of reduced sensitivity to hormone therapy.
Humans ; Turner Syndrome/diagnosis* ; Female ; Pregnancy ; Chromosomes, Human, X/genetics* ; Mosaicism ; Prenatal Diagnosis ; Karyotyping ; Adult ; Karyotype ; Amniocentesis

OBJECTIVE: To investigate the clinical phenotype and genetic etiology of a patient with tall stature and primary amenorrhea presenting with 47,XYY Disorder of sex development (DSD). METHODS: A female patient presenting with "tall stature and primary amenorrhea" at Nanjing Drum Tower Hospital in July 2024 was selected as the study subject. A retrospective study design was employed to collect the patient's clinical data. Peripheral venous blood sample was collected. Following the extraction of genomic DNA, genetic testing was performed including chromosomal karyotyping analysis, copy number variation sequencing (CNV-seq), multiplex PCR for the AZF regions and sex-determining genes Y (SRY), and whole-exome sequencing (WES). Candidate variants were validated by Sanger sequencing and classified for pathogenicity based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of Nanjing Drum Tower Hospital (Ethics No.: 2022-451-01). RESULTS: The patient had a height of 188 cm and a body weight of 50 kg, in addition with infantile uterus, absent ovaries, and primary amenorrhea. G-banded karyotyping analysis of peripheral blood sample revealed 47,XYY. CNV-seq indicated Seq[GRCh37]Yp11.32q12×2. No deletion was detected in the AZF regions of Y chromosome, and SRY was positive. WES identified a heterozygous c.86C>A (p.Thr29Lys) variant of the NR5A1 gene, leading to substitution of threonine with lysine at position 29 of the encoded protein. Sanger sequencing confirmed the presence of the variant. According to the ACMG guidelines, this variant was classified as variant of uncertain significance (VUS) with supporting evidence (PS3_Moderate+PM5+PP3+PM2_Supporting+PS4_Supporting). Reviewing the nearly 60 years of previously reported cases, all 7 documented 47,XYY DSD patients were assigned a female social gender and presented with abnormal gonadal and external genitalia development. Among them, 5 cases underwent SRY testing, all of which were positive. Only 1 case underwent whole-exome sequencing (WES), but no pathogenic or likely pathogenic variants were identified. CONCLUSION This DSD patient presented with the clinical features of tall stature and primary amenorrhea. The NR5A1 gene variant c.86C>A (p.Thr29Lys) probably underlay the Disorder of sex development in this patient. Above finding has enriched the spectrum of pathogenic variants of the NR5A1 gene.
Humans ; Female ; Steroidogenic Factor 1/genetics* ; DNA Copy Number Variations/genetics* ; XYY Karyotype/genetics* ; Karyotyping ; Retrospective Studies ; Phenotype ; Sex Chromosome Disorders of Sex Development/genetics* ; Sex Chromosome Disorders

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 basis, clinical phenotype and pathogenesis for a child with mosaicism ring chromosome 4. METHODS: Clinical data of the child was collected. Peripheral blood chromosomal karyotype G banding analysis, chromosomal microarray analysis (CMA), fluorescence in situ hybridization (FISH) were carried out for the child, in addition with a review of the literature. RESULTS: The child was born full-term with low birth weight, facial dysmorphism, patent ductus arteriosus and ventricular septal defect. His karyotype was determined as mos46,XY,r(4)(p16.3q35.2)[259]/45,XY,-4[25]/47,XY,r(4)(p16.3q35.2), +r(4)(p16.3q35.2)[8]/46,XY,der(4)del(4)(p16.3)inv(4)(p16.3q31.1)[6]/46,XY,dic?r(4;4)(p16.3q35.2;p16.3q35.2)[4]/48,XY,r(4)(p16.3q35.2),+r(4)(p16.3q35.2)×2[3]/46,XY,r(4)(p1?q2?)[2]; CMA result was arr[GRCH37]4p16.3(68 345-2 981 614)×1; FISH result was 45,XY,-4[12]/45,XY,-4×2,+mar1.ish r1(4)(WHS-,D4Z1+)[1]/ 46,XY,-4,+mar1.ishr1(4)(WHS-,D4Z1+)[73]/46,XY,-4,+mar2.ishr2(4)(WHS-,D4Z1++)[1]/47,XY,-4,+mar1×2.ishr1(4) (WHS-, D4Z1+)×2[4]/46,XY,del(4)(p16.3).ish del(4)(p16.3)(WHS-,D4Z1+)[9]. CONCLUSION In this case, the ring chromosome 4 as a de novo variant has produced a number of cell lines during embryonic development and given rise to mosaicism. The clinical phenotype of ring chromosome 4 is variable. The instability of the ring chromosome itself, presence of mosaicism, chromosome breakpoint and range of deletion and/or duplication may all affect the ultimate phenotype.
Humans ; Pregnancy ; Female ; Ring Chromosomes ; In Situ Hybridization, Fluorescence ; Karyotyping ; Karyotype ; Mosaicism

OBJECTIVE: To assess the value of copy number variation sequencing (CNV-seq) for the diagnosis of children with intellectual disability (ID), developmental delay (DD), and autistic spectrum disorder (ASD). METHODS: Forty patients with ID/DD/ASD referred to Nanshan Maternity and Child Health Care Hospital from September 2018 to January 2022 were enrolled. G-banded karyotyping analysis was carried out for the patients. Genomic DNA was extracted from peripheral blood samples and subjected to CNV-Seq analysis to detect chromosome copy number variations (CNVs) in such patients. ClinVar, DECIPHER, OMIM and other database were searched for data annotation. RESULTS: Among the 40 patients (including 30 males and 10 females), 16, 15 and 6 were diagnosed with ID, DD and ASD, respectively. One patient had combined symptoms of ID and DD, whilst the remaining two had combined ID and ASD. Four patients were found with abnormal karyotypes, including 47,XY,+mar, 46,XY,inv(8)(p11.2q21.2), 46,XX,del(5)(p14) and 46,XX[76]/46,X,dup(X)(p21.1q12). Chromosome polymorphism was also found in two other patients. CNV-seq analysis has detected 32 CNVs in 20 patients (50.0%, 20/40). Pathogenic CNVs were found in 10 patients (25.0%), 15 CNVs of uncertain clinical significance were found in 12 patients (30.0%), and 7 likely benign CNVs were found in 4 patients (10.0%). CONCLUSION Chromosome CNVs play an important role in the pathogenesis of ID/DD/ASD. CNV-seq can detect chromosomal abnormalities including microdeletions and microduplications, which could provide a powerful tool for revealing the genetic etiology of ID/DD/ASD patients.
Pregnancy ; Child ; Male ; Humans ; Female ; DNA Copy Number Variations ; Intellectual Disability/genetics* ; Autism Spectrum Disorder/genetics* ; Developmental Disabilities/genetics* ; Abnormal Karyotype

Karyotype analysis is the basic method in cytogenetics, and is also recognized as the "gold standard" for diagnosing chromosomal disorders. The teaching and training for traditional karyotyping analysis is time-consuming and even boring. The individual's ability for mastering the chromosome morphology can vary greatly. Therefore, it is necessary to improve the teaching method. On the basis of the traditional method, we have added auxiliary analysis software during the teaching. This type of splicing karyotype teaching has increased the students' interest and improved their ability for karyotyping, allowing them to quickly remember the characteristic bands of chromosomes. Through enhanced memory of a large number of karyotypic images, the students' ability to recognize individual chromosomes has improved.
Humans ; Karyotyping ; Karyotype ; Cytogenetics ; RNA Splicing ; Software

Humans ; Prognosis ; Leukemia, Myeloid, Acute/genetics* ; Mutation ; Karyotype ; High-Throughput Nucleotide Sequencing

OBJECTIVE: To explore the genetic basis for a Fra(16)(q22)/FRA16B fragile site in a female with secondary infertility. METHODS: The 28-year-old patient was admitted to Chengdu Women's and Children's Central Hospital on October 5, 2021 due to secondary infertility. Peripheral blood sample was collected for G-banded karyotyping analysis, single nucleotide polymorphism array (SNP-array), quantitative fluorescent polymerase chain reaction (QF-PCR) and fluorescence in situ hybridization (FISH) assays. RESULTS: The patient was found to harbor 5 mosaic karyotypes involving chromosome 16 in a total of 126 cells, which yielded a karyotype of mos 46,XX,Fra(16)(q22)[42]/46,XX,del(16)(q22)[4]/47,XX,del(16),+chtb(16)(q22-qter)[4]/46,XX,tr(16)(q22)[2]/46,XX[71]. No obvious abnormality was found by SNP-array, QF-PCR and FISH analysis. CONCLUSION A female patient with FRA16B was identified by genetic testing. Above finding has enabled genetic counseling of this patient.
Female ; Humans ; In Situ Hybridization, Fluorescence ; Chromosome Fragile Sites ; Karyotyping ; Karyotype ; Infertility

OBJECTIVE: To explore the genetic basis for a Chinese pedigree with 6q26q27 microduplication and 15q26.3 microdeletion. METHODS: A fetus with a 6q26q27 microduplication and a 15q26.3 microdeletion diagnosed at the First Affiliated Hospital of Wenzhou Medical University in January 2021 and members of its pedigree were selected as the study subject. Clinical data of the fetus was collected. The fetus and its parents were analyzed by G-banding karyotyping and chromosomal microarray analysis (CMA), and its maternal grandparents were also subjected to G-banding karyotype analysis. RESULTS: Prenatal ultrasound had indicated intrauterine growth retardation of the fetus, though no karyotypic abnormality was found with the amniotic fluid sample and blood samples from its pedigree members. CMA revealed that the fetus has carried a 6.6 Mb microduplication in 6q26q27 and a 1.9 Mb microdeletion in 15q26.3, and his mother also carried a 6.49 duplication and a 1.867 deletion in the same region. No anomaly was found with its father. CONCLUSION The 6q26q27 microduplication and 15q26.3 microdeletion probably underlay the intrauterine growth retardation in this fetus.
Female ; Humans ; Pregnancy ; East Asian People ; Fetal Growth Retardation/genetics* ; Karyotype ; Pedigree ; Prenatal Diagnosis ; Sequence Deletion ; Chromosome Duplication

OBJECTIVE: To explore the genetic characteristics of a child with mosaicism Turner syndrome. METHODS: A child who had presented at Linyi People's Hospital on May 19, 2022 due to short stature was selected as the study subject. The child was subjected to combined chromosomal karyotyping, fluorescence in situ hybridization (FISH), and chromosomal microarray analysis (CMA). RESULTS: The child was found to have a 46,X,i(X)(q10)[94]/45,X[6] karyotype. The result of FISH was nucish(XYpter,XYqter)1[78]/(XYpter)1,(XYqter)3[122]. CMA result for her peripheral blood sample was arr[hg19]Xp22.33p11.1(168551_58526888)×1, and that for her oral mucosal cells was arr[hg19]Xp22.33p11.1(168551_58526888)1-2,Xq11.2q28(63000001_155233098)×2-3. By integrating the above findings, her molecular karyotype was determined as mos 46,X,i(X)(q10)[94]/45,X[6].arr[hg19]Xp22.33p11.1(168551_58526888)×1-2,Xq11.2q28(63000001_155233098)×2-3.nucish(XYpter)1,(XYqter)3[122]/(XYpter,XYqter)1[78], which has indicated mosaicism Turner syndrome. CONCLUSION The 46,X,i(X)(q10)/45,X mosaicism probably underlay the pathogenesis in this child.
Humans ; Child ; Female ; Turner Syndrome/genetics* ; Mosaicism ; In Situ Hybridization, Fluorescence ; Karyotyping ; Karyotype