11/92. 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) |
12/92. 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) |
13/92. Cytogenetic-clinicopathologic correlations in rhabdomyosarcoma: a report of five cases.rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children younger than the age of 15 years. Histologically, RMS can be subdivided into two major subtypes; embryonal (E-RMS) and alveolar (A-RMS) rhabdomyosarcoma, with E-RMS being the more common. Although cytogenetic and molecular genetic findings have been reported extensively for RMS, clinicopathologic-genetic correlations among these tumors have not been reported in detail. In this report, we correlate the cytogenetic findings, including fluorescence in situ hybridization and spectral karyotyping, with pathologic findings and outcome for five RMS, including two A-RMS, one E-RMS, one botryoid RMS, and one anaplastic nonclassified RMS (N-RMS). The findings in A-RMS and E-RMS generally were consistent with previous reports; however, gain of chromosome 7 in A-RMS and gain of chromosome 9 segments in E-RMS observed here have seldom been reported in the literature. Importantly, the botryoid RMS had a cytogenetic profile similar to other types of E-RMS. An add(11)(q21) observed in this tumor, together with a t(8;11)(q12 approximately 13;q21) reported previously, indicates that 11q21 rearrangements may be nonrandomly related to botryoid RMS. In addition, the N-RMS expressed a cytogenetic pattern similar to that observed in E-RMS, thus providing genetic evidence that anaplastic N-RMS is a variant of E-RMS. Finally, these cases provide cogent evidence for the diagnostic and prognostic significance of the pathologic-genetic classification of RMS.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
14/92. 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 = 117.15063070094keywords = preimplantation, embryo (Clic here for more details about this article) |
15/92. A 22/22 translocation carrier with recurrent abortions demonstrated by a Giemsa banding technique,.A 22/22 Robertsonian translocation has been identified in a woman with recurrent abortions by a Giemsa banding technique. Cytogenetic studies of the embryonic tissue derived from one of her spontaneous abortions have demonstrated that the aborted fetus had a 46,XX,-22, t(22q22q) karyotype.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
16/92. Sperm chromosomal abnormalities are linked to sperm morphologic deformities.OBJECTIVE: To describe the association between specific sperm morphologic abnormalities and sperm chromosomal abnormalities on multicolor interphase fluorescence in situ hybridization (FISH). DESIGN: Case report.reproductive medicine unit in a tertiary referral center. PATIENT(S): Three infertile men with severe oligoasthenospermia and total teratozoospermia who were referred for IVF treatment. MAIN OUTCOME MEASURE(S): incidence of spermatozoal chromosomal aneuploidy for chromosome 18 and the sex chromosomes by using FISH. RESULT(S): Morphologic assessment of sperm revealed a high incidence of double heads, multinucleated sperm heads, and multiple tails. Hormone profiles and karyotyping of peripheral lymphocytes were normal in the three men. The proportion of sperm with disomy, trisomy and tetrasomy for chromosome 18, and the sex chromosomes in each patient was 100%, 76%, and 82.5%, respectively. CONCLUSION(S): Specific morphologic abnormalities of sperm may be associated with higher incidence of chromosomal abnormalities. Resolving infertility by offering patients in vitro fertilization/intracytoplasmic sperm injection must be approached with caution because of the significant risk for embryonic aneuploidy and chromosomal abnormalities in any subsequent offspring.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
17/92. Cytogenetic studies in subgroups of rhabdomyosarcoma.rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood and accounts for 10% of all solid tumors in children. There are three different histologic forms of this tumor: embryonal (RMS-E), alveolar (RMS-A), and primitive (RMS-P). Among these, the embryonal form has responded well to chemotherapy. Identification of the correct subtype is important for both the management and treatment of this malignancy. However, the histopathologic classification of RMS is sometimes difficult and distinguishing between the embryonic and primitive forms can present a diagnostic dilemma. Chromosomal abnormalities have been observed in all subtypes. We present the cytogenetic findings in six cases of RMS or related sarcoma. All four cases with RMS-A had both numerical and structural abnormalities in the tumor and involved bone marrow specimens. Three patients had a common marker, t(2;13)(q37;q14), and one patient had a variant marker involving 13q14, t(1;13) (p36;q14), and double minutes (dmin). The single embryonal RMS patient had modal chromosome numbers in the hypertriploid range and extensive structural abnormalities; the t(2;13) was not present, but translocation of 13q to both 1q and 2p was observed, der(1)t(1;13)(q21;q14) and der(2)t(2;13)(p25;q14). The patient with primitive type RMS had a hypodiploid line with several markers, including a complex translocation involving chromosomes 5 and 13 with a breakpoint at 13q14, and t(11;12)(q24;q12), a chromosome marker heretofore found only in Ewing's sarcoma and related tumors. This patient had atypical RMS with mixed neural and myogenic elements. The significance of these chromosomal markers and their importance in the characterization of childhood tumors are discussed, along with a review of the literature.- - - - - - - - - - ranking = 4keywords = embryo (Clic here for more details about this article) |
18/92. SCA17 caused by homozygous repeat expansion in TBP due to partial isodisomy 6.An expanded polyglutamine domain in the TATA-binding protein (TBP) has been described in patients with spinocerebellar ataxia type 17 (SCA17) characterized by cerebellar ataxia associated with dementia. TBP is a general transcription initiation factor that regulates the expression of most eukaryotic genes transcribed by rna polymerase ii. SCA17, as an autosomal dominantly inherited progressive neurodegenerative disorder, is caused by heterozygous expansion of a CAG repeat coding for glutamine. alleles with 27 to a maximum of 44 glutamine residues were found as the normal range, whereas expansions above 45 repeat units were considered pathological. Here, we present a patient with a very severe phenotype with a late onset but rapidly progressing ataxia associated with dementia and homozygous 47 glutamine residues caused by an apparent partial isodisomy 6. This extraordinary case has important implications for the insights of TBP and SCA17. The expanded polyglutamine domain in both TBP copies is not correlated with embryonic death indicating that the normal function of the protein is not disrupted by this kind of mutation but may account for the dementia seen in this patient.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
19/92. Preimplantation genetic diagnosis of chromosome abnormalities: implications from the outcome for couples with chromosomal rearrangements.OBJECTIVES: Chromosomal rearrangements can lead to infertility or repeated spontaneous or induced abortions. The use of preimplantation genetic diagnosis (PGD) allows the selected transfer of chromosomally balanced embryos. The aim of this study was to carry out detailed analysis of the outcome of 11 PGD cycles for 8 patients carrying various chromosomal rearrangements. methods: patients underwent routine in vitro fertilisation with biopsy of embryos on day 3. Specific fluorescent in situ hybridisation protocols were developed for each couple. embryo transfer was possible in all 11 cycles. RESULTS: The outcome was four pregnancies, leading to three live births and one biochemical pregnancy. Post-zygotic mosaicism was detected in 75% of untransferred embryos, the majority of which were chaotic. Detailed follow-up and analysis provided evidence for the co-existence of chromosomally balanced and abnormal cells in six embryos. The mechanisms involved included chromosome breakage and loss of material. CONCLUSIONS: biopsy and analysis of two blastomeres, where possible, reduced the risk of misdiagnosis in cases of balanced/aneuploid mosaics. The three live births achieved for the eight couples treated in this series, despite the poor history in almost all cases, is further proof that a policy of biopsying two cells from embryos consisting of six or more cells and a single cell from four- or five-cell embryos is compatible with a positive outcome.- - - - - - - - - - ranking = 28.430126140189keywords = preimplantation, embryo (Clic here for more details about this article) |
20/92. prenatal diagnosis of a supernumerary aberrant chromosome 9.For counselling of parents, as well as to basically understand how chromosome aneuploidies affect embryonic or fetal development, it is of great importance to analyse and collect genotypes of fetuses with clinical anomalies. This report describes the first prenatal diagnosis of a supernumerary chromosome 9 with deletion of the chromosome region 9q34. Ultrasound examination in the 13th week of gestation detected increased nuchal translucency of 6.9 mm, fetal ascites and a pronounced facial anomaly. Hysteroscopic examination before curettage made it possible to describe this facial anomaly as a double-sided, median defect of the superior lip with protrusion of parts of intersegments. This report provides evidence that the absence of trisomy 9 in 9q34 does not prevent abnormal facial development.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
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