OBJECTIVE: To delineate a small supernumerary marker chromosome (sSMC) derived from chromosome 9 with combined cytogenetic and molecular methods. METHODS: For a pregnant woman with fetal ultrasound revealing left ventricular punctate hyperechoic echo, and a high risk for monosomy or partial deletion of chromosome 8, chromosome 9 trisomy, monosomy or partial deletion of chromosome 11 by non-invasive prenatal testing, and an abnormal MOM value revealed by mid-term serum screening, amniocentesis was performed for G banded chromosomal analysis and single nucleotide polymorphism array (SNP-array) assay. Peripheral blood samples of the woman and her spouse were also collected for the above tests. In addition, the woman was further subjected to C banding karyotyping analysis and fluorescence in situ hybridization (FISH) assay. RESULTS: The G-banded karyotype of the pregnant women was 47,XX,+mar[20]/46,XX[80], whilst C-banding analysis showed a deep stain in the middle of the sSMC (suggestive of centromeric region) and light stain at both ends (suggestive of euchromatism). FISH combined with DAPI banding analysis using 9pter/9qter probes revealed a karyotype of 47,XX,+mar.ish i(9)(9p10)(9p++)[2]/46,XX[18], whilst SNP-array has revealed a 68.1 Mb duplication in the 9p24.3q13 region. A database search has suggested the duplication to be likely pathogenic. No abnormality was found in her fetus and spouse by karyotyping and SNP-array analysis. CONCLUSION Through combined cytogenetic and molecular genetic analysis, a sSMC derived from chromosome 9 was delineated, which has enabled genetic counseling for the couple.
Female ; Humans ; Pregnancy ; Biomarkers ; Chromosomes, Human, Pair 9/genetics* ; Genetic Testing ; In Situ Hybridization, Fluorescence ; Monosomy

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*

OBJECTIVE: To explore the genetic basis for a neonate with Pierre-Robin sequence. METHODS: The child was subjected to chromosomal karyotyping, single nucleotide polymorphism array (SNP-array)-based comparative genomic hybridization and fluorescence in situ hybridization (FISH) analysis. RESULTS: The child has featured microgthnia, glossoptosis, upper airway obstruction, mandible dehiscence and short neck. He was found to have a karyotype of 46,XY,der(4)add(4)(q34). Her mother's karyotype was determined as 46,XX,t(1;4)(q43;q34), while his father was 46,XY. SNP-array analysis suggested the child to be arr [hg19] 1q42.2q44 (232 527 958-249 202 755)× 3; 4q34.3q35.2 (168 236 901-190 880 409)× 1. The result of SNP-array for both parents was normal. FISH analysis confirmed that his mother has carried a balanced t(1;4)(q42;34) translocation. The aberrant chromosome 4 in the child has derived from his mother's translocation, which gave rise to partial 1q trisomy and 4q monosomy. CONCLUSION The 1q42.2q44 duplication and 4q34.3q35.2 deletion of the child probably underlay his abnormal phenotype of Pierre-Robin sequence.
Child ; Comparative Genomic Hybridization ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Infant, Newborn ; Male ; Monosomy ; Pierre Robin Syndrome/genetics* ; Translocation, Genetic ; Trisomy/genetics*

OBJECTIVE: To investigate the frequency, karyotype characteristics and prognosis significance of monosomal karyotype (MK) in newly diagnosed MDS patients. METHODS: The clinical, laboratorial and follow-up data of 202 MDS patients received the chromosome karyotype test in Department of Hematology, Ningbo Hospital of Zhejiang University from 2009 to 2018 were analyzed retrospectively, the monosomal karyotype features, clinical characteristics and their effects on the prognosis of MDS patients also were analyzed. RESULTS: Among 202 cases of MDS, 25 (12.38%) confirmed to be the MK. The abnormality of chromosome 5 (60.00%), 7 (56.00%), 17 (56.00%), 15 (56.00%), 13 (40.00%) and 20（40.00%）were common in monosomal karyotype. MK-MDS (MDS with monosomal karyotype) patients had higher bone marrow blast percentage than MK-MDS (MDS without monosomal karyotype) patients, the median are 6.25% and 3.00% (P＜0.01) respectively, but there were no difference in age, sex, hemoglobin level, white blood cell count, neutrophile granulocyte percentage, platelet count, blood blast percentage, serum ferritin, folic acid and vitaminB12 between MK-MDS and MK-MDS. The overall survival time of MK-MDS and MK-MDS patiens with chromosome 3, 5, 7, 13, 15, 17 abnormalities was significantly shorter than MK-MDS and AK+MK-MDS patients (MDS with abnormal karyotype but without monosomal karyotype) , the MK-MDS patients had a median survival time of 7.33 months, but the median survival time had not been reached in MK-MDS and AK+MK-MDS patients had not been reached by the end of the follow-up, and could not be assessed (P＜0.01). CONCLUSION The monosomal karyotype is a poor prognosis factor for newly-diagnosed MDS patients. The poor prognosis suggested by monosomal karyotype may be related with the abnormality of 3, 5, 7, 13, 15 and 17 chromosome.
Humans ; Karyotype ; Karyotyping ; Monosomy ; Myelodysplastic Syndromes ; Prognosis ; Retrospective Studies

OBJECTIVE: To explore the genetic cause for a patient with intellectual disability, short stature and multiple congenital anomalies, and to correlate the result with the clinical phenotype. METHODS: Routine karyotyping analysis was carried out on GTG-banded metaphase chromosomes. Single nucleotide polymorphism (SNP) microarray was used to detect microdeletions or microduplications in the patient. Fluorescence in situ hybridization (FISH) was used to ascertain the origin of aberrant chromosomes. RESULTS: The karyotype of the patient was 46,XY,der(18), while both of his parents had a normal karyotype. SNP array identified a 1.23 Mb deletion at 18p11.32-pter (chr18: 136 227-1 370 501, hg19) and a 33.76 Mb duplication at 18q21.1-qter (chr18: 44 250 359-78 013 728, hg19) in the patient. Above finding was confirmed by dual-color FISH with one color for 18p and another for 18q. The patient presented with some common features of 18p deletion and 18q duplication including intellectual disability and growth retardation, in addition with some features of 18p deletion including pectus excavatum, short stature and growth hormone (GH) deficiency. The patient showed progressive improvement of stature with GH therapy. Comparison of patients with previously reported dup(18q)+del(18p) recombinations suggested that, even for patients with similar breakpoints, their phenotypes have ranged from normal to severe and there were no consistent findings. CONCLUSION As aberrations involving double chromosomal segments often result in phenotypic variability, it has been difficult to correlate the genotype of our patient with his phenotype.
Abnormalities, Multiple ; Chromosome Deletion ; Chromosomes, Human, Pair 18 ; Genotype ; Humans ; In Situ Hybridization, Fluorescence ; Karyotyping ; Monosomy ; Phenotype ; Trisomy

OBJECTIVE: To determine the nature and origin of aberrant chromosomes in a child with multiple anomalies and psychomotor retardation. METHODS: Routine G-banding was carried out to analyze the karyotypes of the patient and his parents, and next generation sequencing for copy number variations (CNV-seq) was used for the fine mapping of the aberrant chromosomal regions. RESULTS: The proband and his uncle exhibited psychomotor retardation, craniofacial malformation, infantile external genitalia, and concealed penis. Cytogenetic analysis indicated that the child has a 46,XYqh+,+(9),t(9;13)(q13;q12),pat,-13 karyotype. His uncle was XYqh+,+(9),t(9;13)(q13;q12)mat,-13, his father was 46,XYqh+,t(9;13)(q13;q12)mat, his grandmother was 46,XX,t(9;13)(q13;q12), and his grandfather was 46,XYqh+. The result of CNV-seq assay for the child was 46,XY,+9p(pter-p13.2,-40 Mb×3). No deletion was detected. CONCLUSION The partial trisomy 9 and partial monosomy 13 probably underlie the phenotypic abnormalities in the child. Combined chromosomal karyotyping and DNA sequencing can facilitate delineation of the nature and origin of the aberrant chromosomes.
Abnormalities, Multiple ; Child ; Chromosome Deletion ; Chromosomes, Human, Pair 13 ; Chromosomes, Human, Pair 9 ; DNA Copy Number Variations ; Humans ; Karyotyping ; Male ; Monosomy ; Pedigree ; Translocation, Genetic ; Trisomy

Turner syndrome (TS) is a chromosomal disorder caused by monosomy of the X chromosome, with complete or partial absence of the second sex chromosome. Anomalies of root morphology have been found to occur more often in patients with TS, which make endodontic treatment challenging and requires special handling. The patients with TS may also have systematic problems such as cardiac or renal malformations, so in treating these patients it is important for clinicians not only to be aware of the characteristic intraoral findings, but also to make the patients have regular dental check-ups to prevent oral complications in advance.An 12-year-old girl who had been diagnosed with TS at the age of 10 years was referred due to discomfort in the bilateral mandibular premolar regions. Dens evaginatus and taurodontism were detected in all the mandibular premolars characteristically. The bilateral mandibular first premolars had three roots and the bilateral mandibular second premolars had periapical lesion with two roots. Due to the complexity of the root canal anatomy, root canal treatment were completed with a dental microscope to ensure adequate visualization. After 2 years of regular follow-up examinations, there were no clinical sign or symptom associated with the teeth, and no periapical lesion, was found.This case report describes the characteristic oral features and dental management of TS patients.
Bicuspid ; Child ; Chromosome Disorders ; Dental Pulp Cavity ; Female ; Follow-Up Studies ; Humans ; Monosomy ; Sex Chromosomes ; Tooth ; Turner Syndrome ; X Chromosome

OBJECTIVETo explore the limitation of non-invasive prenatal testing (NIPT) technique through analyzing two false negative cases.

METHODSChromosomal karyotyping analysis was performed on umbilical cord blood sample derived from case 1 at 24 weeks' gestation and peripheral blood sample derived from the neonate of case 2. Placental tissues of case 1 and peripheral blood sample of case 2 were also analyzed by high-throughput sequencing for copy number variations (CNVs).

RESULTSFor case 1, analysis of fetal umbilical cord blood sample showed a translocation type of trisomy 21, i.e., 46,XY,der(21;21)(q10;q10),+21. There were no obvious abnormalities detected at or near the center of the fetal surface and matrix surface of the placenta. High-thoroughput sequencing showed Chr13:(33 840 001 - 115 100 000)×3[60%]/46,XY[40%] at the edge of the placenta, Chr13:(34 080 001-115100000)×3[54%]/46,XY[46%] at the edge of placenta matrix surface, and trisomy 21 in the umbilical cord tissue. For case 2, analysis of the neonatal peripheral blood sample showed a karyotype of 46,XY,del(18)(q22), which revealed a microdeletion in chromosome 18. High-throughput sequencing of the maternal peripheral blood sample stored during pregnancy confirmed it to be chr18: (62 910 000 - 78 020 000)×1 with 15.1 Mb deletion in the fetus. The neonate was therefore diagnosed with partial monosomy of chromosome 18.

CONCLUSIONFalse negative results of NIPT are related with the fraction of circulating cell-free fetal DNA in the maternal serum. NIPT has limitations in detecting fetal chromosomal microdeletion and confined placenta mosaicisms. Routine ultrasound scan is necessary for pregnant women with low-risk indicated by NIPT.

Adult ; Aneuploidy ; Chromosomes, Human, Pair 18 ; Diagnostic Errors ; Female ; High-Throughput Nucleotide Sequencing ; Humans ; Karyotyping ; Monosomy ; Pregnancy ; Prenatal Diagnosis ; methods

OBJECTIVETo analyze a girl with moderate mental retardation and speech and language disorders with cytogenetics technique and next-generation sequencing (NGS).

METHODSG-banding chromosome analysis was used to ascertain the karyotype of the child and her parents, and NGS was used for determining the size and origin of the abnormal chromosome fragment. Mate-pair and PCR were used to determine its parental origin.

RESULTSThe karyotype of the child was determined to be 46,XX,add(1)(q44)dn, while her parents were both normal. NGS revealed that the child has harbored a partial trisomy of 6q24.3-q27, and the breakpoint was mapped to at 6q24.3q27. In addition, a 2.5 Mb microdeletion at 1q44 was found in the patient.

CONCLUSIONNo recognizable phenotype was associated with 1q44 deletion. The abnormal phenotypes presented by the child may be attributed to the 6q24.3-q27 triplication. Compared with conventional cytogenetic analysis, NGS has a much higher resolution and great accuracy.

Adult ; Child ; Chromosome Banding ; Chromosome Disorders ; genetics ; Chromosomes, Human, Pair 1 ; genetics ; Chromosomes, Human, Pair 6 ; genetics ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Intellectual Disability ; genetics ; Male ; Monosomy ; genetics ; Trisomy ; genetics

Turner syndrome is the most common chromosomal disorder in girls. Various phenotypic features show depending upon karyotype from normal female through ambiguous genitalia to male. Usually, Turner girls containing 45,X/46,XY mosaicism, or sex-determining region Y (SRY) gene may have mixed gonadal dysgenesis with various external sexual differentiation. We experienced a short statured 45,X Turner girl with normal external genitalia. Because SRY gene was positive, laparoscopic gonadectomy was performed. The dysgenetic gonads revealed bilateral ovotesticular tissues. The authors report a mixed gonadal dysgenesis case found in clinical 45,X Turner patient with positive SRY gene. Screening for SRY gene should be done even the karyotype is 45,X monosomy and external genitalia is normal.
Chromosome Disorders ; Disorders of Sex Development ; Female ; Genes, sry* ; Genitalia ; Gonadal Dysgenesis, Mixed* ; Gonads ; Humans ; Karyotype ; Male ; Mass Screening ; Monosomy ; Mosaicism ; Sex Differentiation ; Turner Syndrome*