Paracentric inversion of chromosome 18 is a rare cytogenetic abnormality. The vast majority of paracentric inversions are harmless and the offspring of paracentric inversion carriers have only slightly elevated risks for unbalanced karyotypes. However, various clinical phenotypes are seen due to breakpoint variation or recombination. We report a prenatally detected case of familial paracentric inversion of chromosome 18, inv(18)(q21.1q22), with normal clinical features.
Chromosome Aberrations ; Chromosomes, Human, Pair 18 ; Karyotype ; Phenotype ; Recombination, Genetic

Paracentric inversion of chromosome 18 is a rare cytogenetic abnormality. The vast majority of paracentric inversions are harmless and the offspring of paracentric inversion carriers have only slightly elevated risks for unbalanced karyotypes. However, various clinical phenotypes are seen due to breakpoint variation or recombination. We report a prenatally detected case of familial paracentric inversion of chromosome 18, inv(18)(q21.1q22), with normal clinical features.
Chromosome Aberrations ; Chromosomes, Human, Pair 18 ; Karyotype ; Phenotype ; Recombination, Genetic

OBJECTIVETo study the genetic basis of aberrant crypt foci (ACF), which serve as a very early morphological alteration during the development of carcinogenesis by analyzing the loss of heterozygosity (LOH).

METHODSDNA from 35 colorectal carcinomas (CRC) and 34 matched ACF were isolated by microdissection. LOH of microsatellite loci at 18q12, 18q21, 5q12, 5q21, 3p21, 2p16, 17q21, 17q11 and 11p13 was detected by means of ABI-SEQUENCER and GeneScan software was applied for analysis.

RESULTSThe rate of LOH in ACF (41.18%) was less than that in carcinoma (68.57%) (P < 0.05). The profile of LOH rates at loci 18q12, 5q12, 3p21, 17q21, 17q11, 11p13 and 2p16 in ACF was similar to that in carcinoma. The LOH frequencies on 18q12, 18q21, 5q12, 5q21, and 3p21 were higher than that on 17q11 and 11p13. However the rate at 18q21 and 5q21 in ACF was much lower than that in the carcinoma (P < 0.05). The co-existing carcinomas displayed more polypoid growth pattern and located more at the sigmoid colon and rectum. LOH in carcinomas did not correlate with the location, size, type of the carcinoma and Duke's stage.

CONCLUSIONSACF are putative preneoplastic lesions that might represent the earliest morphological lesion with the alteration at molecular genetic level. Our study provides further genetic evidence in the pathogenesis of colorectal carcinomas.

Chromosomes ; Chromosomes, Human, Pair 11 ; Chromosomes, Human, Pair 17 ; Chromosomes, Human, Pair 18 ; Chromosomes, Human, Pair 2 ; Chromosomes, Human, Pair 3 ; Chromosomes, Human, Pair 5 ; Colorectal Neoplasms ; genetics ; pathology ; Humans ; Loss of Heterozygosity ; Precancerous Conditions

Child, Preschool ; Chromosomes, Human, Pair 18 ; Female ; Human Growth Hormone ; deficiency ; Humans ; Ring Chromosomes

This article aimed to report two cases of Burkitt lymphoma/leukemia with concurrent t(8;14) and t(14;18). Morphology, immunophenotype, cytogenetics and molecular biology (MICM) methods were applied to diagnosis. The results showed that the two cases were both acute lymphocytic leukemia L3 type according to FAB criteria. Conventional cytogenetic technique or interphase fluorescence in situ hybridization (FISH) demonstrated that t(8;14) and t(14;18) were detected concurrently in both patients. CD20, CD10, FMC7, CD38 and CD19 were expressed in both patients by immunophenotyping. According to MICM, they were both diagnosed as Burkitt lymphoma/leukemia. The first patient died in one month after chemotherapy, and the second patient survived 19 months after rituximab- combined high-dose chemotherapy and subsequently allogeneic hematopoietic stem cell transplantation (HSCT). In conclusion, t(8;14) and t(14;18) may present simultaneously in Burkitt lymphoma/leukemia and indicate poor prognosis. Rituximab-combined chemotherapy and subsequently HSCT could improve the outcomes of such cases.
Burkitt Lymphoma ; genetics ; Chromosomes, Human, Pair 14 ; genetics ; Chromosomes, Human, Pair 18 ; genetics ; Chromosomes, Human, Pair 8 ; genetics ; Female ; Humans ; Lymphoma ; genetics ; Male ; Middle Aged ; Translocation, Genetic

OBJECTIVETo evaluate the feasibility of using fluorescence in situ hybridization(FISH) for the detection of a few common chromosome aneuploidies on interphase nuclei of uncultured amniotic fluid cells.

METHODSAmniotic fluid samples were taken from 55 women at 16-32 weeks of pregnancy; interphase FISH was performed for diagnosing Down syndrome and aneuploidies of other four chromosomes 13, 18, X and Y. Then the karyotypes from standard cytogenetic analysis after percutaneous umbilical blood sampling(PUBS) were compared to the FISH results.

RESULTSEach of the 55 uncultured amniotic fluid samples tested with FISH was enumerated 200 nuclei. Fifty-three samples were normal. Two samples were found to have trisomy 21(one is a case of standard trisomy 21 with three signals in all 200 nuclei, the other is a mosaic trisomy 21).

CONCLUSIONInterphase FISH analysis of uncultured amniotic fluid cells is a rapid, accurate and very sensitive method. It could be used in the prenatal cytogenetic laboratory.

Adult ; Amniocentesis ; Amniotic Fluid ; cytology ; Aneuploidy ; Chromosomes, Human, Pair 13 ; Chromosomes, Human, Pair 18 ; Chromosomes, Human, Pair 21 ; Chromosomes, Human, X ; Chromosomes, Human, Y ; Down Syndrome ; diagnosis ; genetics ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Pregnancy ; Prenatal Diagnosis ; methods ; Trisomy

Edwards syndrome, also called trisomy 18, is one of the most common autosomal anomalies. The survival rate of patients with Edwards syndrome is very low and its characteristic findings include cardiac malformations, mental retardation, growth retardation, specific craniofacial anomalies, clenched hands, rocker-bottom feet, and omphalocele. Compared with the classic Edwards syndrome, the symptom of partial duplication of chromosome 18 is relatively mild with a good prognosis. We report the case of a baby with partial duplication 18q11.2-q12. The characteristic phenotype features of Edwards syndrome were observed in the patient. However, the symptom was milder than the typical Edwards syndrome. At present, we can expect better prognosis for this patient.
Chromosomes, Human, Pair 18 ; Foot ; Hand ; Hernia, Umbilical ; Humans ; Intellectual Disability ; Phenotype ; Prognosis ; Survival Rate ; Trisomy

OBJECTIVE: To determine the fetal aneuploidy in fetal blood cells from cordocentesis. METHODS: We analyzed their karyotype and performed fluorescence in situ hybridization(FISH) for chromosome 18, 21, X, and Y in 14 cases of fetal blood cells from cordocentesis at Department of Obstetrics & Gynecology, College of Medicine, Seoul National University and Hamchoon Women's Clinic. RESULTS: In all cases we obtained the consistent results in both methods and were able to rapidly detect aneuploidy in uncultured fetal blood cells using FISH before karyotyping with culture for 48 hr. The averages for accuracy of FISH were from 84.6 % to 93.9%. CONCLUSION: In this study we suggest that the rapid detection in uncultured fetal blood using FISH is possible and that this diagnostic method will be clinically useful when rapid result would be demanded.
Aneuploidy* ; Chromosomes, Human, Pair 18 ; Cordocentesis ; Fetal Blood* ; Fluorescence* ; Gynecology ; In Situ Hybridization* ; Karyotype ; Karyotyping ; Obstetrics ; Seoul

Chromosomes, Human, Pair 18 ; Female ; Fertilization in Vitro ; Humans ; Infant, Newborn ; Trisomy

OBJECTIVE To analyze a neonate with multiple malformations and to correlate its genotype with phenotype. METHODS The karotypes of the child and her parents were subjected to G-banding chromosome analysis, and array comparative genomic hybridization (array-CGH) was used for fine mapping of the aberrant region. RESULTS The karyotype of the child was ascertained as 46,XX,del(18)(p11.2). Array CGH has identified a 9.8 Mb deletion at 18p11.32-p11.22. The patient has presented features such as holoprosencephaly, choanal atresia, heart defect, and craniofacial dysmorphisms. CONCLUSION The de novo 18p deletion probably underlies the main clinical manifestations of the child.
Abnormalities, Multiple ; genetics ; Chromosome Banding ; Chromosome Deletion ; Chromosomes, Human, Pair 18 ; Female ; Humans ; Infant, Newborn ; Phenotype