1/43. Analysis of the sex chromosome constitution of sperm in men with a 47, XYY mosaic karyotype by fluorescence in situ hybridization.OBJECTIVE: To determine the incidence of sex chromosome aneuploidy in the sperm of two men with a 47,XYY/46,XY karyotype. DESIGN: Case report. SETTING: infertility clinic in a teaching hospital. PATIENT(S): One patient with near normal semen parameters whose wife had a history of miscarriages and one patient with primary infertility and severe oligoasthenozoospermia. INTERVENTION(S): cytogenetic analysis of peripheral lymphocytes and three-color X/Y/18 fluorescence in situ hybridization analysis of sperm. MAIN OUTCOME MEASURE(S): Analysis of sex chromosome disomy and diploidy rates in sperm. RESULT(S): Both patients had a 47,XYY/46,XY karyotype. The hyperdiploidy rate of patient 1 was 19% and that of patient 2 was 90%. The incidence of disomy XY was significantly elevated in both patients compared with the controls (0.23% and 1.02%, respectively, versus 0.10%). The incidence of disomy YY (0.44% versus 0.10%) was increased only in patient 2, as was the incidence of disomy 18 (0.49% versus 0.09%) and the rate of diploidy (0.83% versus 0.13%). The rate of 24,XX sperm in both patients was not different from that in the controls. CONCLUSION(S): patients with a 47,XYY mosaic karyotype may be at risk of producing offspring with a hyperdiploid sex constitution. These patients should have their sperm investigated by fluorescence in situ hybridization to determine their particular risks before they undergo intracytoplasmic sperm injection.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/43. fluorescence in-situ hybridization of sex chromosomes in spermatozoa and spare preimplantation embryos of a Klinefelter 46,XY/47,XXY male.It has been suggested recently that 47,XXY germ cells are able to progress through meiosis to produce hyperhaploid spermatozoa. We report on a 46,XY/47,XXY Klinefelter patient whose spermatozoa were recovered from the ejaculate and used for intracytoplasmic sperm injection (ICSI). fluorescence in-situ hybridization (FISH) analysis of the patient's spermatozoa and of spare preimplantation embryos with dna probes specific for chromosomes X, Y and 18 revealed sex chromosome hyperploidy in 3.9% of the sperm nuclei analysed (2.23% XY18, 1.12% XX18, 0.56% YY18), while only three out of 10 spare embryos analysed were normal for chromosomes tested. The abnormalities included two diploid mosaic embryos with the majority of the blastomeres normal for the chromosomes tested, and five embryos with mostly abnormal blastomeres and chaotic chromosome X, Y and 18 patterns. None of the embryos analysed showed a XXY1818 or XXX1818 chromosome complement. The frequency of sex chromosome hyperploidy in the spermatozoa of the mosaic Klinefelter patient was higher than the mean reported for karyotypically normal males, supporting the hypothesis that 47,XXY germ cells are able to complete meiosis and produce aneuploid spermatozoa. However, most of the spermatozoa analysed were normal for sex chromosomes, and ICSI of the patient's spermatozoa did not result in a spare embryo with a uniform 47,XXY or 47,XXX chromosome complement. Instead, fertilization produced a high percentage of mosaic embryos with chaotic chromosome arrangements.- - - - - - - - - - ranking = 0.83333333333333keywords = hybridization (Clic here for more details about this article) |
3/43. Duplication of chromosome region 8p23.1-->p23.3: a benign variant?Chromosome analysis was performed in a 34-year-old man who was phenotypically normal except for oligoasthenozoospermia. In this patient, analysis of GTG-banded chromosomes showed in one chromosome 8 additional chromosomal material of unknown origin. To characterize the aberrant chromosome more precisely, a paint specific for chromosome region 8pter-->8p23.1 was generated by microdissection and degenerated oligonucleotide primed-polymerase chain reaction (DOP-PCR) and used as fluorescence in situ hybridization (FISH) paint. After reverse painting, hybridization signals were only found on the short arm of the two chromosomes 8, with an enlarged signal on the derivative chromosome 8. The duplication was characterized further with band-specific FISH probes. We concluded that (part of) chromosome region 8p23.1-->p23.3 was duplicated. Chromosome analysis of the parents showed that the dup(8) was of maternal origin and that the fertile brother of the index patient also was a carrier of the chromosome aberration. There was no history of miscarriages. We suggest that duplication of region 8p23.1-->p23.3 can be regarded as euchromatic variant or duplication with no phenotypic effect.- - - - - - - - - - ranking = 0.33333333333333keywords = hybridization (Clic here for more details about this article) |
4/43. Breakpoint of a y chromosome pericentric inversion in the DAZ gene area. A case report.BACKGROUND: The presence of a spermatogenesis locus (gene or gene complex) in the euchromatic region of the long arm of the y chromosome (Yq11), defined as azoospermia factor on the basis of gross structural rearrangement, was detected. The gene family responsible for different spermatogenetic defects is "deleted in azoospermia" (DAZ). CASE: A 34-year-old man had oligozoospermia, and a cytogenetic analysis carried out on peripheral lymphocytes with G banding revealed a 46,X, inv(Y)(p11q11)karyotype. The relation between the chromosomal breakpoint and the DAZ gene was more precisely defined by a fluorescent in situ hybridization technique. We revealed two signals for the DAZ gene, weaker than normal, one on the short arm and the other on the long arm of the y chromosome, indicating that the breakpoint was located at the DAZ gene level. CONCLUSION: This is the first report documenting a chromosomal pericentric inversion with disruption in the DAZ gene area. We hope to obtain information on whether the disruption affects a functional zone of the gene and correlates with oligospermia at the chromosomal level.- - - - - - - - - - ranking = 0.16666666666667keywords = hybridization (Clic here for more details about this article) |
5/43. Pericentric inversion of the y chromosome of infertile male.The authors report a case with pericentric inversion of the y chromosome associated with asthenonecrozoospermia. The conventional karyotype was 46, X, inv (Y) (p11q11). polymerase chain reaction (PCR) analysis revealed the deletion of DYZ3, DYS139, and RBM1. Three-color fluorescent in situ hybridization (FISH) analysis of the sperm chromosomes showed normal ratio between X- and Y-bearing sperm. In this case, the frequencies of aneuploidy of the sperm are not significantly higher compared with those from the normal volunteers. Cytogenetic analysis is recommended when the patients with pericentric inversion of the y chromosome are attending an infertility clinic.- - - - - - - - - - ranking = 0.16666666666667keywords = hybridization (Clic here for more details about this article) |
6/43. Deletion of RBM and DAZ in azoospermia: evaluation by PRINS.Molecular and cytogenetic studies from infertile men have shown that one or more genes controlling spermatogenesis are located in proximal Yq11.2 in interval 6 of the y chromosome. Microdeletions within the azoospermia factor region (AZF) are often associated with azoospermia and severe oligospermia in men with idiopathic infertility. We evaluated cells from a normal-appearing 27-year-old man with infertility and initial karyotype of 45,der(X)t(X;Y)(p22.3;p11.2)[8]/46,t(X;Y)(p22.3;p11.2)[12]. By fluorescence in situ hybridization with dual-color whole chromosome paint probes for X and Y chromosomes, we confirmed the Xp-Yp interchange. By primed in situ labeling, we identified translocation of the SRY gene from its original location on Yp to the patient's X chromosome at band Xp22. We also obtained evidence that the apparent marker was a der(Y) (possibly a ring) containing X and Y domains, and observed that the patient's genome was deleted for RBM and DAZ, two candidate genes for AZF.- - - - - - - - - - ranking = 0.16666666666667keywords = hybridization (Clic here for more details about this article) |
7/43. Sperm analysis by FISH in a case of t(17; 22) (q11; q12) balanced translocation: case report.Individual sperm from men with balanced translocations have different chromosomal contents. Thus, an estimation of the overall sperm chromosomal imbalance of such patients could help to give the couple an adapted genetic counselling. We report here the study of a balanced translocation carrier, t(17;22) (q11;q12) whose reproductive history reported four miscarriages. Moreover, he had an abnormal semen analysis with oligoteratozoospermia. The meiotic segregation pattern was examined in 700 sperm, using fluorescence in-situ hybridization (FISH). Nineteen percent of the sperm had balanced translocations or were normal. All other sperm were unbalanced (81%) and their distribution was observed as follows: the frequencies of adjacent 1, adjacent 2 and 3:1 segregations were 12.9, 5.8 and 46.8% respectively. Among the segregations scored, 13.7% were related to second meiotic division abnormalities. Less than 2% of the total sperm scored were not explained. The 3:1 segregation was present at a very high rate, which is very unusual. In cases of balanced translocations, we believe that no general features can be drawn. Thus, the FISH technique may be very helpful for genetic counselling, which remains an important step and must be done with care.- - - - - - - - - - ranking = 0.16666666666667keywords = hybridization (Clic here for more details about this article) |
8/43. Molecular and cytogenetic characterization of an azoospermic male with a de-novo Y;14 translocation and alternate centromere inactivation.BACKGROUND: Y-autosome (Y/A) translocations have been reported in association with male infertility. Different hypotheses have been made as to correlations between Y/A translocations and spermatogenetic disturbances. We describe an azoospermic patient with a de-novo Y;14 translocation: 45,X,dic(Y;14)(q12;p11). methods AND RESULTS: Cytogenetic, fluorescent in-situ hybridization (FISH) and molecular studies have been performed. A 14/22 (D14Z1/D22Z1) centromere and a Y centromere (DYZ1) probe both showed a signal on the translocation chromosome, confirming its dicentricity. Each copy of the translocation chromosome had only one primary constriction, with inactivation of the Y centromere in most (90%) of the cells. The 14 centromere was inactive in the remaining cells (10%). FISH and molecular deletion mapping analysis allowed acute assignment of the Yq breakpoint to the junction of euchromatin and heterochromatin (Yq12), distal to the AZF gene location (Yq11). CONCLUSIONS: This study supports the hypothesis that in Y/A translocations infertility might be related to meiotic disturbances with spermatogenetic arrest. In addition, sex chromosome molecular investigations, performed on single spermatids, suggest a highly increased risk of producing chromosomally abnormal embryos.- - - - - - - - - - ranking = 0.16666666666667keywords = hybridization (Clic here for more details about this article) |
9/43. FISH analysis of y chromosome long arm deletions in subfertile men considering ICSI. A report of two cases.BACKGROUND: Men with y chromosome long arm deletions, resulting in infertility, form a very significant group of patients, with a view to treatment. With recent advances in assisted reproductive techniques, it is expected that if these patients undergo intracytoplasmic sperm injection, their male offspring will inherit the same deleted regions of Y chromosomes. Hence, characterization of these deleted Y regions provides information, allowing patients to make informed decisions about reproduction. fluorescence in situ hybridization (FISH), with probes along the y chromosome, is very helpful in identification of the exact breakpoints. CASES: Two men with complaints of infertility on examination showed low or no sperm in their semen samples. Routine cytogenetic analysis of the peripheral blood showed a small marker chromosome. This marker was identified as the y chromosome by FISH. Subsequently, other probes along the Y long arm were used to characterize the extent of the deletion. CONCLUSION: With the use of fluorescence-labelled probes, it was possible to identify the extent of the Y chromosome deletion. The distal Yq11 region had been lost in both patients, resulting in oligospermia and azoospermia. Characterizing markers by FISH gave good guidelines to the patients about the possible effects on offspring, allowing them to make appropriate decisions.- - - - - - - - - - ranking = 0.16666666666667keywords = hybridization (Clic here for more details about this article) |
10/43. An azoospermic male with an unbalanced autosomal-Y translocation.An azoospermic male with an unbalanced translocation between the y chromosome and chromosome 15 was examined in the present study. Testicular biopsy found only sertoli cells only within the seminiferous tubules of the 35-year-old patient. Chromosome analysis, using the techniques of G and C banding and fluorescent in situ hybridization revealed an abnormal karyotype of 46,XY,der(15)t(Y;15)(q12;p11). Deoxyribonucleic acid (DNA) analysis confirmed the presence of the genes such as DAZ and YRRM1 which are known to control spermatogenesis. The cause of spermatogenetic dysfunction in this particular patient therefore.- - - - - - - - - - ranking = 0.16666666666667keywords = hybridization (Clic here for more details about this article) |
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