ABSTRACT
A two-year-and-eight-month-old girl presented with clitoromegaly and short stature. Two cell lines, 45,X and 46,X,idic(Y)(q11.2), were observed. Cytogenetic and fluorescence in situ hybridisation investigations were carried out on her peripheral lymphocytes and gonadal cells, to determine the genotype-phenotype effect with respect to differential tissue distribution, effects of the sex determining region of the Y chromosome, and the break-points in the azoospermia factor region.
Subject(s)
Chromosomes, Human, Y/genetics , Gonadal Dysgenesis, Mixed/genetics , Mosaicism , Turner Syndrome/genetics , Child, Preschool , Clitoris/abnormalities , Female , Gonadal Dysgenesis, Mixed/diagnosis , Humans , Spectral Karyotyping/methods , Turner Syndrome/diagnosisABSTRACT
OBJECTIVE: To identify the mosaic marker chromosome detected in amniotic fluid cells of a 26-year-old woman, with raised triple test values and an ultrasound scan, which showed a fetus with echogenic bowels. METHODS: Routine karyotyping with G- and C-banding was carried out for both, amniotic fluid at 18 weeks of gestation as well as fetal blood at 22(+6) weeks. Peripheral blood of both parents was karytoyped. MFISH and the all centromeric human probe were used on fetal lymphocytes to identify the marker chromosome. RESULTS: Both parents had a normal karyotype. Amniotic fluid culture showed a de novo supernumerary marker chromosome (SMC) in 14 of the 30 colonies from four different cover slip cultures. The marker was confirmed in 50% of the fetal lymphocytes. G- and C-banding provided little information except that the marker had some heterochromatic material. The all centromeric human probe also showed the presence of a centromere along with a rim of euchromatic material. MFISH identified this ring marker to be belonging to chromosome 8. CONCLUSIONS: SMCs with chromosome 8 have been shown to be variable phenotypes. Presence of only heterochromatic material seems to have no discernable phenotypic effects, but, with the presence of euchromatic material, mental and physical developmental delay has been reported. The parents opted to go ahead with the pregnancy and an apparently normal female baby was born at 40 weeks with no complications.
Subject(s)
Amniocentesis , Aneuploidy , Chromosomes, Human, Pair 8 , Karyotyping/methods , Spectral Karyotyping/methods , Adult , Amniotic Fluid/cytology , Chromosome Banding , Female , Genetic Markers/genetics , Humans , Male , Mosaicism , Pregnancy , Ring ChromosomesABSTRACT
Eight semen samples from men with teratozoospermia (T), along with samples from 3 men with normal fertility and 5 samples from men with oligoasthenoteratozoospermia (OAT) were analyzed for X and Y chromosomal anomalies with the use of fluorescently labeled centromeric probes. This study was undertaken to determine whether patients with abnormal sperm morphology (teratozoospermia) have increased or decreased incidence of a sex chromosomal anomaly. The sex chromosome disomy for the T samples was 0.36% and for the OAT group it was 0.61%, compared with baseline value for the normozoospermia group (0.09%).
Subject(s)
Oligospermia/genetics , Sex Chromosome Aberrations , Spermatozoa/cytology , Adult , Humans , In Situ Hybridization, Fluorescence , MaleABSTRACT
A 14-year-old Chinese female presenting with primary amenorrhoea and poorly developed secondary sexual characteristics is described here. Cytogenetic analysis showed the presence of one normal X along with a dicentric X which had a duplication of the entire chromosome from the band Xp22.1 to Xqter. She was karyotyped as 46, XX, psu dic X (p22.1) (Xqter:Xp22.1::Xp22.1:Xqter), a variant of Turner syndrome. Both parents and a younger sister had normal karyotypes. FISH with X centromeric probes was a useful test for confirmation of the two centromeres and also in ruling out the presence of a monosomic or normal diploid X cell line.
Subject(s)
Body Height/genetics , Turner Syndrome/genetics , X Chromosome/genetics , Adolescent , Female , Humans , In Situ Hybridization, Fluorescence , Karyotyping , PhenotypeABSTRACT
The presence of abnormal ultrasound markers showing a thick nuchal fold with short middle phalanx of the fifth finger in an otherwise normal-appearing female fetus led to the sampling of amniotic fluid at 16 weeks gestation. Cytogenetic analysis with routine G-banding showed a 45,X karyotype in all 20 cells analysed from two flasks. However, fluorescent in situ hybridization on uncultured cells showed presence of a Y signal in 9 cells, 11 cells showing a single signal for the X. A cytogenetic analysis of the fetal blood at 23 weeks confirmed the presence of two cell lines, 45,X and 46,X, idic(Y)(p11). The couple opted to have the pregnancy terminated. However, the fetus was not available to carry out confirmatory tests.
Subject(s)
Amniotic Fluid/cytology , Chromosome Aberrations , Cytogenetic Analysis , In Situ Hybridization, Fluorescence , Mosaicism , X Chromosome , Y Chromosome , Female , Fetal Blood/cytology , Gestational Age , Humans , PregnancyABSTRACT
AIMS: The aims of this study was to invent the prevalence of cisterna magna (CM) enlargement in a low-risk population and relate this to chromosomal abnormalities and initial delivery outcome. STUDY DESIGN: 11,145 patients having routine ultrasound scan at 21st week of pregnancy were screened for abnormalities. Cases with CM enlargement were traced and outcome retrieved either from case notes or from the patients. RESULTS: In our low-risk population six fetuses were found to have CM enlargement. Only one had a chromosomal abnormality, 47XY + 18, and this fetus also presented with other malformations. Four were healthy at birth and one, also with other malformations, is showing signs of mental retardation. All cases were male. CONCLUSION: Isolated CM enlargement does not seems to be an indicator for chromosomal abnormalities, especially if the fetus is a male. Still, it should alert the examiner of the possibility of other malformations, which may be of importance.
Subject(s)
Chromosome Aberrations , Cisterna Magna/diagnostic imaging , Ultrasonography, Prenatal , Adult , Congenital Abnormalities/genetics , Female , Humans , Intellectual Disability/genetics , Karyotyping , Male , Pregnancy , Risk Factors , SingaporeABSTRACT
OBJECTIVE: To identify the site of fetal blood sampling (FBS) with lesser complications; and also analyses the reasons for targetting the intrahepatic vein (IHV) for FBS. METHODS: Fetal blood sampling (FBS) performed on 382 women over a period of 7 years at the National University Hospital, Singapore was analysed. FBS was performed from 13 weeks of gestational age onwards. In 76.4% (292 of 382) the intrahepatic part of the umbilical vein (IHV) was targetted; in 18.3% (70 of 382) percutaneous umbilical cord sampling (PUBS) was performed; in 5.2% (20 of 382) cardiocentesis was performed to obtain fetal blood. RESULTS: Multivariate analysis showed an increase in odds of fetal loss for umbilical cord and cardiocentesis groups compared with the IHV FBS group. It was statistically significant (p < 0.01) only in the cardiocentesis group for fetal loss at < 2 weeks of performing the procedure.
Subject(s)
Fetal Blood/physiology , Hepatic Veins/embryology , Prenatal Diagnosis/methods , Female , Fetal Death/etiology , Gestational Age , Hepatic Veins/physiology , Humans , Maternal Age , Multivariate Analysis , Odds Ratio , Pregnancy , Pregnancy Outcome , Prenatal Diagnosis/adverse effects , Regression Analysis , Retrospective Studies , Ultrasonography, Prenatal , Umbilical Veins/embryology , Umbilical Veins/physiologyABSTRACT
Serous fluids from cystic hygromas, pleural effusions, and ascites are an easily accessible and plentiful source of lymphocytes. The feasibility and reliability of using these as alternative sources to conventional amniotic fluid or fetal blood cultures have been studied here. In some cases of prenatal diagnosis, especially in pregnancies complicated by the presence of cystic hygromas and fetal hydrops, obtaining amniotic fluid or fetal blood can be difficult due to obstruction by the cyst or oligohydramnios. A total of 14 cases with fetal hydrops detected ultrasonigraphically between 15 and 33 weeks of pregnancy over a period of 1 year have been subjected to conventional amniotic fluid or fetal blood karyotyping, along with samples of fluids from cystic hygromas, ascites or pleural effusions as obtained. Pleural fluids (n = 4), cystic hygroma fluids (n = 5), and ascitic fluids (n = 6) were obtained. The culture failure rate was low, 2/14. Karyotypically, two of the fluids, both from cystic hygromas, were 45,X; the rest were normal. A rapid 1-day additional test of fluorescent in situ hybridization (FISH) was carried out on uncultured cells of the alternative fluids using probes for the most commonly occurring aneuploidies, 13, 18, 21, X and Y, with good results.
Subject(s)
Ascitic Fluid/pathology , Lymphangioma, Cystic/pathology , Lymphocytes/ultrastructure , Pleura/cytology , Prenatal Diagnosis/methods , Cells, Cultured , Female , Follow-Up Studies , Gestational Age , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Lymphocytes/cytology , PregnancyABSTRACT
Fluorescent in-situ hybridization (FISH) is becoming more and more relevant as an important future tool in prenatal and pre-implantation genetic diagnosis and cancer cytogenetics. This review describes the FISH technique as applied to whole chromosome spreads and interphase cells and discusses its applications in clinical cytogenetics. Information is presented on the various types of probes and the subsequent hybridization and detection procedures. The potential use of this novel FISH technique in the diagnosis of numerical and structural chromosomal aberrations in routine karyotyping for prenatal diagnosis, tumour cytogenetics and pre-implantation genetic diagnosis is outlined.
