No abstract available.
Mass Screening*

No abstract available.
Mass Screening*

No abstract available.

No abstract available.
Flow Cytometry* ; Microscopy*

No abstract available.
Flow Cytometry* ; Microscopy*

No abstract available.
Blood Donors* ; Chungcheongnam-do* ; Humans

Ring chromosome 21 causes a multitude of phenotypes, ranging from severe abnormalities to normal. The proposed mechanism of ring formation, breakage of both short and long arms of a chromosome with subsequent end to end fusion, remains unproven. We encountered a 4-year-old boy who presented developmental delay, microcephaly, micrognathia, hypertelorism, low-set ears, mild optic nerve hypoplasia, cleft lip and palate, scoliosis and left foot valgus, but normal brain MRI. Chromosome study from peripheral blood showed 46,XY, r(21)(p11.2q22.1) karyotype. The authors report the first case of ring chromosome 21 in Korea with a review of the literature.
Arm ; Brain ; Child, Preschool ; Cleft Lip ; Ear ; Foot ; Humans ; Hypertelorism ; Karyotype ; Korea ; Magnetic Resonance Imaging ; Male ; Microcephaly ; Optic Nerve ; Palate ; Phenotype ; Ring Chromosomes* ; Scoliosis

Chromosomal microarray analysis (CMA) enables the genome-wide detection of submicroscopic chromosomal imbalances with greater precision and accuracy. In most other countries, CMA is now a commonly used clinical diagnostic test, replacing conventional cytogenetics or targeted detection such as FISH or PCR-based methods. Recently, some consensus statements have proposed utilization of CMA as a first-line test in patients with multiple congenital anomalies not specific to a well-delineated genetic syndrome, developmental delay/intellectual disability, or autism spectrum disorders. CMA can be used as an adjunct to conventional cytogenetics to identify chromosomal abnormalities observed in G-banding analysis in constitutional or acquired cases, leading to a more accurate and comprehensive assessment of chromosomal aberrations. Although CMA has distinct advantages, there are several limitations, including its inability to detect balanced chromosomal rearrangements and low-level mosaicism, its interpretation of copy number variants of uncertain clinical significance, and significantly higher costs. For these reasons, CMA is not currently a replacement for conventional cytogenetics in prenatal diagnosis. In clinical applications of CMA, knowledge and experience based on genetics and cytogenetics are required for data analysis and interpretation, and appropriate follow-up with genetic counseling is recommended.
Child ; Autism Spectrum Disorder ; Chromosome Aberrations ; Coat Protein Complex I ; Consensus ; Cytogenetics ; Diagnostic Tests, Routine ; Genetic Counseling ; Genomic Structural Variation ; Humans ; Microarray Analysis ; Mosaicism ; Prenatal Diagnosis ; Statistics as Topic

BACKGROUND: The bcr-abl gene rearrangement is a very important genetic marker in at least 95% of cases of chronic myeloid leukemia (CML). The technique that allows the detection of bcr-abl gene rearrangement seem to be the testing for the diagnoses and the detection of minimal residual disease (MRD) and may help in monitoring patients. Recent introduction of real-time quantitative PCR should eventually allow actual quantification of the target gene during amplification. In the present study, we investigated bcr-abl chimeric mRNA quantification in CML after bone marrow transplantation (BMT) by real-time RT-PCR and its clinical applicability to the decision of therapeutic intervention. METHODS: The subjects were a consecutive series of 9 CML patients with serial quantification of bcr-abl chimeric mRNA by real-time RT-PCR in peripheral blood or bone marrow aspirates. The sensitivity of real-time RT-PCR was compared to conventional RT-PCR and then the correlation with FISH results was analyzed. RESULTS: Seventeen bone marrow samples and 40 peripheral bloods were obtained from patients. The sensitivity of real-time RT-PCR was 10(-6) and positive signals were detected in negative cases by conventional RT-PCR. A significant correlation between the bcr-abl/G6PDH ratio by real-time RT-PCR and the proportion of positive cells for bcr-abl gene rearrangement by FISH was obtained (r=0.64). In the serial blood and bone marrow specimens, we found a progressive decrease in the bcr-abl/G6PDH ratio in all the patients. CONCLUSIONS: Our findings indicated that quantitative analysis of bcr-abl chimeric mRNA by real-time RT-PCR might be a useful tool for the monitoring of minimal residual disease in bcr-abl positive leukemic patients.
Bone Marrow ; Bone Marrow Transplantation* ; Diagnosis ; Gene Rearrangement ; Genetic Markers ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive* ; Neoplasm, Residual ; Polymerase Chain Reaction ; Real-Time Polymerase Chain Reaction* ; RNA, Messenger