1/6. Lymphoproliferative disorder of fetal origin presenting as oligohydramnios.lymphoma involving the placenta or fetus remains a very rare event. All cases reported to date have shown the lymphoma cells to be of maternal origin in that the tumor cells have preferentially involved the intervillous spaces with sparing of the villi and fetal circulation. We report a novel case of a monoclonal primary placental Epstein-Barr virus (EBV)-associated B-cell lymphoma of fetal origin. The placenta of a 20-week stillborn fetus born to a 19-year-old gravida 1 para 0 woman, presenting with oligohydramnios, showed a large cell infiltrate confined within villi and sparing the intervillous spaces, indicative of preferential involvement of the fetal circulation. Necropsy did not show any other site of involvement by malignant lymphoma or other abnormalities. Immunophenotypic studies showed the tumor cells to be of B-cell phenotype with a relatively high proliferation rate. EBV EBER1 rna was identified in more than 95% of tumor cells, and polymerase chain reaction studies showed EBV EBNA1 strain type A and wildtype EBV LMP1. Analysis of the immunoglobulin heavy chain by polymerase chain reaction showed a monoclonal B-cell population. in situ hybridization studies using a commercially available probe directed at repeated sequences on the human y chromosome showed a single intense signal within trophoblastic epithelium and lymphoma cells, indicative of male origin. The mother remains in good health 11 months after delivery.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/6. Bilateral renal agenesis and fetal ascites in association with partial trisomy 13 and partial trisomy 16 due to a 3:1 segregation of maternal reciprocal translocation t(13;16)(q12.3; p13.2).A female fetus with bilateral renal agenesis and fetal ascites was found to have partial trisomy 13 (pter-q12.3) and partial trisomy 16 (p13.2-pter), 47,XX, der(13)t(13;16)(q12.3; p13.2)mat. The chromosomal aberration was due to a 3:1 segregation with tertiary trisomy transmitted from a maternal reciprocal translocation 13;16. Prenatal ultrasound of a 29-year-old, gravida 2, para 0 woman at 22 gestational weeks showed fetal ascites, severe oligohydramnios and non-visualization of fetal urinary bladder and kidneys. The pregnancy was terminated. At delivery, the proband displayed dysmorphic features of hypertelorism, a prominent glabella, epicanthic fold, a stubby nose with a depressed nasal bridge, anteverted nares, thin lips, micrognathia, low-set ears, a short neck and a distended abdomen. Necropsy confirmed bilateral renal agenesis and ascites. A cytogenetic study performed on fibroblasts obtained from the proband's skin revealed an extra supernumerary chromosome. The mother was later found to have a reciprocal translocation. fluorescence in situ hybridization for a submicroscopic deletion in chromosome 22q11 in the proband was negative. The parents had no urological anomalies. Our observation further extends the clinical spectrum associated with proximal trisomy 13q and distal trisomy 16p. We suggest prenatal cytogenetic analysis in fetuses with urological anomalies, including renal agenesis, to uncover underlying genetic disorders.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/6. Double aneuploidy involving trisomy 7 with Potter sequence.We report a prenatal case of double aneuploidy (consisting of chromosome 7 and X) with the features of Potter sequence. Of the stillborn fetus, skin fibroblast cultures were performed and fluorescence in situ hybridization (FISH) technique was also used for further investigation. On physical examination; the fetus was found to have malformed ears, micrognatia, hypertelorism, abnormal extremities, rocker-bottom feet and abnormal external genitalia and polycystic right kidney was seen after an extensive autopsy. As amniocentesis and cordocentesis materials revealed x chromosome mosaicism, trisomy 7 was detected in the skin fibroblast culture of the ex fetus and karyotype evaluated as composite; 46~47,X, 7,-X[cp18]. FISH results confirmed the double aneuploidy and also revealed XX and XXXX cell lines. Comparison with the previously reported cases of trisomy 7 with Potter syndrome suggests a possible link (if not coincidental) between trisomy 7 and Potter syndrome in our case. This is the first reported case of double aneuploidy involving trisomy 7 with the features of Potter syndrome.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/6. Rapid exclusion of chromosomal aneuploidies by fluorescence in situ hybridization prior to fetal surgery for obstructive uropathy--a case report.Ultrasound of a fetus at 17 weeks gestation revealed posterior urethral valve syndrome with anhydramnios. fluorescence in situ hybridization (FISH) to detect aneuploidies of chromosomes 13, 18, 21, X and Y was performed on transitional cells from the fetal bladder obtained at percutaneous vesicocentesis, followed by conventional cytogenetics. Fetal urine was chosen due to unavailability of amniotic fluid for karyotypic analysis. A nonlethal (disomic) karyotype was suggested by FISH, and thus placement of a vesicoamniotic shunt was performed. The ability to prognosticate in cases of obstructive uropathy is not absolute, and fetal surgery for relief of urinary obstruction is best performed at the earliest possible gestational age. Thus, all available means for rapidly ruling out lethal congenital anomalies should be undertaken in cases of obstructive uropathy prior to any decision regarding fetal surgery.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
5/6. Isolation of cosmids corresponding to the chromosome breakpoints of a de novo autosomal translocation, t(6;19)(p21;q13.1), in a patient with multicystic renal dysplasia.hydronephrosis caused by pelvi-ureteric junction obstruction (PUJO) is a frequent urological malformation assumed to result from a deficient development of the ureteric bud. The exact etiology of pelvi-ureteric junction stenosis is unknown, but there is convincing evidence for a genetic cause, with linkage analysis predicting a hereditary hydronephrosis locus on chromosome 6p. We encountered a patient with a de novo autosomal t(6;19)(p21;q13.1) and attendant bilateral multicystic renal dysplasia (MRD), bilateral PUJO resulting in massive hydronephrosis, and an associated von Mayer-Rokitansky-Kuster disorder. On the basis of the presumption that in this patient the putative hydronephrosis gene might be disrupted by the translocation, we sought to isolate dna from the breakpoint regions as the initial step in a strategy to identify genes affected by the t(6; 19). Using sequential rounds of fluorescence in situ hybridization (FISH) with cosmids selected from a detailed integrated map of the long arm of chromosome 19, we have identified a cosmid clone that spans the breakpoint. The position of the breakpoint was further localized by Southern blot analysis. Using a vectorette PCR approach, rearranged dna fragments were isolated and, by comparative nucleotide sequence analysis, these were shown to contain ectopic sequences. A cosmid clone containing these ectopic sequences was isolated and shown by CASH (chromosome assignment using somatic cell hybrids) and FISH (fluorescence in situ hybridization) analysis to map to the short arm of chromosome 6 and to span the breakpoint found in the MRD patient. The isolated cosmid clones are useful reagents for analysis of other MRD patients and for the search for genes at or flanking the breakpoints.- - - - - - - - - - ranking = 2keywords = hybridization (Clic here for more details about this article) |
6/6. Renal abnormalities on obstetric ultrasound as a presentation of digeorge syndrome.We describe three pregnancies that presented with renal anomalies on obstetric ultrasound as the main abnormality and were subsequently found to have interstitial deletions within chromosome 22q11. A cardiac defect, double-outlet right ventricle, was also seen in the first case. Amnio infusion was refused in the second pregnancy and the perimembranous ventricular septal defect was not identified prior to termination. In the third case, there was no cardiac defect. The genitourinary abnormalities were a right hydroureter and hydronephrosis with a ureterocele bulging into the bladder lumen, bilateral multicystic kidneys with associated oligohydramnios, and a left multicystic kidney with right renal agenesis and associated oligohydramnios. Absence of thymus at autopsy in all three cases led to fluorescent in situ hybridization studies looking for the submicroscopic deletion of chromosome 22q11 associated with digeorge syndrome.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |