1/36. Sperm analysis in a subfertile male with a Y;16 translocation, using four-color FISH.Sperm analysis was performed in a male with oligoasthenoteratozoospermia (OAT) and a reciprocal t(Y;16) (q11. 21;q24), using four-color FISH. Intracytoplasmic sperm injection (ICSI) treatment in this patient had resulted in the birth of one chromosomally balanced and two chromosomally normal children. To assess the risk of having a chromosomally unbalanced conception after ICSI, morphologically normal spermatozoa were studied with a set of probes allowing detection of all segregation variants. There were 51% normal or balanced sperm cells. The fraction of sperm products resulting from alternate and adjacent I segregation was 87%, 12% were products of 3:1 disjunction, and the other 1% had other types of aneuploidy. If morphologically abnormal cells were also included in the FISH analysis, nearly 90% of all the spermatozoa were unbalanced. We conclude that although the majority of males with a Y/autosome translocation are infertile due to azoospermia, our patient produces sufficient morphologically and chromosomally normal spermatozoa to have chromosomally normal or balanced offspring after ICSI. Assuming that ICSI with an unbalanced spermatozoon from this patient would result in a nonviable embryo in many cases, the combination of in vitro and subsequent in vivo selection probably results in a risk of unbalanced offspring of much less than 50%. Hence, FISH studies on the sperm of translocation carriers are useful for estimating the risk of having unbalanced offspring after ICSI and in understanding the mechanisms underlying infertility in such carriers.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
2/36. Mosaic trisomy 17 in amniocytes: phenotypic outcome, tissue distribution, and uniparental disomy studies.mosaicism for trisomy 17 in amniocyte cultures is a rare finding, whilst postnatal cases are exceptional. In order to gain insight into the possible effects of the distribution of the trisomic line and of uniparental disomy (UPD) on embryofoetal development, we have performed follow-up clinical, cytogenetic and molecular investigations into three newly detected prenatal cases of trisomy 17 mosaicism identified in cultured amniotic fluid. In the first case, the pregnancy ended normally with the birth of a healthy girl, and analysis of newborn lymphocytes and of multiple extra-embryonic tissues was indicative of confined placental mosaicism. The second case was also associated with a normal pregnancy outcome and postnatal development, and only euploid cells were found in peripheral blood after birth. However, maternal isodisomy 17 consequent to a meiosis II error and loss of a chromosome 17 homologue was detected in peripheral lymphocytes postnatally. In the third case, pathological examination after termination of pregnancy showed growth retardation and minor dysmorphisms, and the trisomic line was detected in foetal skin fibroblasts. In addition, biparental derivation of chromosome 17 was demonstrated in the euploid lineage. These results, together with previously reported data, indicate that true amniotic trisomy 17 mosaicism is more commonly of extra-embryonic origin and associated with normal foetal development. Phenotypic consequences may arise when the trisomic line is present in foetal tissues. Case 2 also represents the first observation of maternal UPD involving chromosome 17; the absence of phenotypic anomalies in the child suggests that chromosome 17 is not likely to be subject to imprinting in maternal gametes.- - - - - - - - - - ranking = 3keywords = embryo (Clic here for more details about this article) |
3/36. Non-invasive exclusion of fetal aneuploidy in an at-risk couple with a balanced translocation.A pregnant woman who was a carrier for a balanced chromosome translocation [46,XX, t(1;6) (p31;q14)] and who had had six miscarriages, declined invasive testing but agreed to non-invasive prenatal diagnosis by analysis of fetal cells in maternal blood. Monoclonal antibody (Mab) against the zeta (z) and gamma (gamma) chains of embryonic and fetal haemoglobin were used to identify fetal nucleated erythrocytes (FNRBC). There were no FNRBC detected at 7 weeks, one anti-z-positive FNRBC was detected at 11 weeks, and 12 anti-gamma-positive FNRBC were detected at 20 weeks. Fluorescent in-situ hybridization was performed using probes for chromosomes X, Y, 1 and 6 to identify fetal gender and the presence of an unbalanced chromosomal translocation. A tentative prenatal diagnosis was made of a female fetus disomic for chromosomes 1 and 6. A female infant with a 46,XX karyotype was born at term. This is the first attempt of exclusion of a chromosome translocation using fetal cells isolated from maternal blood. There is an advantage of using fetal cells isolated from maternal blood for non-invasive prenatal diagnosis in couples who have a history of multiple miscarriages due to a parental translocation, and who decline invasive testing in a pregnancy that continues to the second trimester.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
4/36. Gonadal pathology in triploidy.There are numerous reports describing the pathology of the fetus and placenta in triploidy. Although gonadal pathology is described in many of these reports, consistent changes have not been noted nor is it clear whether genital ambiguity can be considered part of the triploid phenotype. We present a case of triploidy of probable diandric origin, in which there were dysgenetic gonads with abnormal seminiferous tubules, nodules of undifferentiated stroma, and focal absence of the tunica albuginea. As this finding was distinctly unusual in our experience of triploid gonadal pathology, we reviewed the gonadal histology in 51 fetal and infant triploids examined in our autopsy/embryopathology laboratory. The gonads were compared to age-matched normal controls to determine if there was a specific gonadal pathology associated with triploidy and if there was any correlation of this pathology with parental origin of the triploidy. Our review of the triploid gonads indicated that while minor, nonspecific changes were not uncommon, overtly dysgenetic gonads, as observed in the index case, are rare.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
5/36. Solid variant of alveolar rhabdomyosarcoma with unbalanced t(2;13) and hypotetraploidy, without MYCN amplification.The histological subtype of alveolar rhabdomyosarcoma (AR) is characterised by the cytogenetic translocation t(2;13)(q35;q14) in approximately 70% of cases, a rearrangement rarely present in the embryonal rhabdomyosarcoma (ER) subtype. The MYCN gene is amplified in some cases of AR. We present a young man with an unusual pattern, namely solid variant of AR with hypotetraploidy and the t(2;13) in an unbalanced form. The MYCN gene was not amplified on FISH, but showed increased copy number, consistent with ploidy.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
6/36. Meiotic segregation analysis by FISH investigation of spermatozoa of a 46,Y,der(X),t(X;Y)(qter-->p22::q11-->qter) carrier.Chromosome analysis performed on a 30-year-old man revealed a 46,Y,der(X),t(X;Y)(qter-->p22::q11-->qter) karyotype, confirmed by fluorescence in situ hybridization (FISH). The man was of short stature, and no mental retardation was noticed; genitalia and testes were normal, as were the patient's FSH, LH, and testosterone blood levels. Sperm analysis showed azoospermia at the time of the first sampling and severe oligozoospermia, with 125,000 spermatozoa/milliliter, at the time of the second sampling. The sperm gonosomal complement of this patient and of a 46,XY donor were analyzed using multicolor FISH with X- and Y-chromosome probes. Our results clearly indicated that germinal cells carrying the translocation are able to complete the meiotic process by producing spermatozoa compatible with normal embryonic development, with more than 80% of the spermatozoa having either a y chromosome or a der(X); however, a high level of spermatozoa with gonosomal disomies was observed. We also found a significant increase in the frequency of autosomal disomies in the carrier, which would suggest an interchromosomal effect. All previously reported cases in adult males were associated with azoospermia; testicular histological studies, performed in patients carrying the same X;Y translocation, showed spermatogenetic arrest after pachytene. To our knowledge, this is the first molecular analysis of the gonosomal complement in spermatozoa of men with a t(X;Y)(qter-->p22::q11-->qter).- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
7/36. Preimplantation genetic diagnosis of pericentric inversions.Inversions are structural chromosome abnormalities that may be associated with infertility, multiple miscarriage and chromosomally unbalanced offspring. Preimplantation genetic diagnosis (PGD) with subtelomeric probes was used to select for transfer only those embryos that were normal or balanced for three pericentric inversions. In contrast to previous protocols the present procedure allows the detection of unbalanced embryos that might arise from U-recombination in the inverted region. Additionally, aneuploidy screening was carried out in two cases by a second round of fluorescent in situ hybridization (FISH) with centromeric probes. Of the three couples that underwent the procedure one became pregnant twice. The first pregnancy delivered a healthy and chromosomally normal baby and the second pregnancy is ongoing with triplets.- - - - - - - - - - ranking = 2keywords = embryo (Clic here for more details about this article) |
8/36. Demonstration of a mechanism of aneuploidy in human oocytes using Multifluor fluorescence in situ hybridization.OBJECTIVE: To evaluate the potential of Multifluor fluorescence in situ hybridization (M-FISH) for karyotyping the human oocyte and first polar body. DESIGN: Prospective case study. SETTING: research laboratories, university hospital. PATIENT(S): A 33-year-old woman with polycystic ovary syndrome who was undergoing ovarian stimulation and ICSI. MAIN OUTCOME MEASURE(S): karyotyping of all chromosomes within an oocyte and first polar body, using GV stage oocytes matured to metaphase II in vitro. RESULT(S): Oocyte hyperploidy was diagnosed by M-FISH to be 23, X 15 cht 19 cht 22 cht. The correspond- ing polar body was hypoploid, with a karyotype of 23, X -15 cht -19 cht -22 cht. This was due to unbalanced predivision at meiosis I. Reprobing confirmed karyotype assignments for chromosomes X, 13, 18, and 21. CONCLUSION(S): The mechanism involved in maternally derived aneuploidy can be defined by using M-FISH to simultaneously karyotype both oocyte and first polar body chromosomes at metaphase II. Multifluor FISH may be useful for investigative studies of maternally derived aneuploidy, which is a major cause of preimplantation waste in natural and assisted reproduction.- - - - - - - - - - ranking = 71.108828358262keywords = preimplantation (Clic here for more details about this article) |
9/36. Localized pleural malignant mesothelioma.Pleural malignant mesothelioma (PMM) is a rare tumor and it is commonly seen in the form of multiple nodules or a diffuse tumor. A localized tumor mass in the pleura is extremely rare. Only seven cases have been reported. In this report, we present an additional case of localized PMM and describe the immunohistochemical and flow cytometric findings. A 61-year-old woman, without a history of smoking or asbestos exposure, presented with a severe pain in her right shoulder and arm. Chest radiography showed a solitary mass in the right upper lung field. Computed tomography showed a 5 cm right upper lung mass. magnetic resonance imaging showed that the mass extended to the wall of the thorax. The patient underwent surgery for total removal of the tumor. pathology revealed a localized malignant mesothelioma. Immunohistochemical analysis showed that the tumor was strongly and diffusely positive for cytokeratins with high and low molecular weight, and focally positive for vimentin and epithelial membrane antigen (EMA), but it was negative for carcinoembryonic antigen, factor viii, alpha-fetoprotein and Leu-M1. flow cytometry showed an aneuploid dna content in the tumor. The final diagnosis was localized malignant mesothelioma (epithelial type). The patient showed signs of local recurrence 5 months after surgery, and radiotherapy was given.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
10/36. First clinical application of comparative genomic hybridization and polar body testing for preimplantation genetic diagnosis of aneuploidy.OBJECTIVE: To develop a preimplantation genetic diagnosis (PGD) protocol that allows any form of chromosome imbalance to be detected.DESIGN: Case report employing a method based on whole-genome amplification and comparative genomic hybridization (CGH).SETTING: Clinical IVF laboratory.PATIENT(S): A 40-year-old IVF patient.INTERVENTION(S): Polar body and blastomere biopsy.MAIN OUTCOME MEASURE(S): Detection of aneuploidy.RESULT(S): Chromosome imbalance was detected in 9 of 10 polar bodies. A variety of chromosomes were aneuploid, but chromosomal size was found to be an important predisposing factor. In three cases, the resulting embryos could be tested using fluorescence in situ hybridization, and in each case the CGH diagnosis was confirmed. A single embryo could be recommended for transfer on the basis of the CGH data, but no pregnancy ensued.CONCLUSION(S): Evidence suggests that preferential transfer of chromosomally normal embryos can improve IVF outcomes. However, current PGD protocols do not allow analysis of every chromosome, and therefore a proportion of abnormal embryos remains undetected. We describe a method that allows every chromosome to be assessed in polar bodies and oocytes. The technique was accurate and allowed identification of aneuploid embryos that would have been diagnosed as normal by standard PGD techniques. As well as comprehensive cytogenetic analysis, this protocol permits simultaneous testing for multiple single-gene disorders.- - - - - - - - - - ranking = 360.54414179131keywords = preimplantation, embryo (Clic here for more details about this article) |
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