Cases reported "Oligospermia"

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1/20. 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.
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2/20. Unique (Y;13) translocation in a male with oligozoospermia: cytogenetic and molecular studies.

    The incidence of Y/autosome translocations is low. Whereas involvement of non-acrocentric chromosomes often leads to infertility, cases related with acrocentric chromosomes are usually familial with no or minimal effect on fertility. A de novo (Yp/13p) translocation was found in a 32-year-old male referred for severe oligozoospermia. Conventional cytogenetic procedures (GTG, CBG and NOR banding) and molecular cytogenetic techniques (fluorescence in situ hybridization, FISH) were performed on high-resolution chromosomes obtained after peripheral blood lymphocyte culture as also on interphase nuclei of spermatogenic cells from semen samples. Screening of AZF microdeletions in the Yq11.2 region known to be involved with spermatogenesis defects was also performed. GTG banding showed a (Yp/13p) translocation in all scored metaphases. CBG and NOR staining of the derivative chromosome revealed the maintenance of Yq heterochromatin and of the 13p NOR region. FISH with centromeric Y and 13/21 probes, SRY specific probe and X/Y (p and q arms) sub-telomeric probes gave the expected number/location of fluorescent signals. Hybridisation with a pan-telomeric repeat (TTAGGG) probe showed an absence of the telomeric sequences at the fusion point of the rearranged chromosome. FISH analysis with probes to chromosomes X, Y, 13 and 18 showed an abnormal segregation of the translocated chromosome during meiosis I, which explains that only 13.6% of the secondary spermatocytes were normal. Most of these became arrested, as after meiosis II the large majority of the round spermatids were normal (70%), as were in consequence most of the sperm (85.1%). Multiplex-PCR confirmed the intactness of the SRY region and showed absence of AZF microdeletions. We report a novel de novo (Yp;13p) translocation characterised by loss of the 13p and Yp telomeres. Meiotic studies using FISH demonstrated meiosis I chromosome unpairing and mal segregation that justifies the severe oligozoospermia. Although most sperm have a normal chromosomal constitution, preimplantation genetic diagnosis should be considered an option for this patient.
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3/20. ICSI and the transmission of X-autosomal translocation: a three-generation evaluation of X;20 translocation: case report.

    Published reports show that male carriers of an X-autosome translocation, which is either inherited from their mother or is de novo, are generally sterile, regardless of the position of the breakpoint in the X chromosome. We report a three-generation propagation of such a translocation in a family with a case of male factor infertility. Due to the condition of severe oligozoospermia, the proband and his wife underwent ICSI, which resulted in the birth of a normal healthy female. Cytogenetic (chromosome) analyses and X-chromosome inactivation (XCI) assays were done on the family. The cytogenetic analysis of the proband, a man with severe oligozoospermia, revealed an X-autosomal translocation, 46,Y,t(X;20)(q10;q10), which was inherited from his mother. His brother had the same translocation. amniocentesis and post-natal umbilical cord analyses revealed that the female infant carried the same translocation as her father. XCI studies showed highly skewed inactivation of the normal X chromosome in the female infant, her paternal grandmother, and her mother who had a normal karyotype. In contrast to the data from the literature, our study suggests that men with a certain type of X-autosomal translocation could conceive children through ICSI in conditions in which a few spermatogonia are able to complete meiosis II. The literature involving X-autosomal translocation in males is also reviewed and the importance of the study of X-chromosomal inactivation in female infants discussed.
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4/20. meiosis I arrest and azoospermia in an infertile male explained by failure of formation of a component of the synaptonemal complex.

    OBJECTIVE: To characterize the early stages of meiosis in a male with unexplained azoospermia. DESIGN: Case report. SETTING: Case Western Reserve University and University hospitals of Cleveland. PATIENT(S): A 30-year-old male with nonobstructive azoospermia. INTERVENTION(S): Immunostaining for components of the synaptonemal complex and recombination-associated proteins, fluorescence in situ hybridization (FISH) for specific chromosomes. MAIN OUTCOME MEASURE(S): Progression to and through pachytene of meiosis I in controls and in the patient. RESULT(S): We observed complete meiosis I arrest in the patient, associated with failure of formation of the mature, tripartite synaptonemal complex. CONCLUSION(S): Abnormalities in synaptonemal complex formation are responsible for a proportion of cases of unexplained male infertility.
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5/20. Meiotic defects in a man with non-obstructive azoospermia: case report.

    Infertile men have an increased frequency of aneuploid sperm. We have determined that decreased recombination is associated with the production of aneuploid sperm in humans. The aim of this study was to determine whether some cases of infertility are associated with decreased meiotic recombination. Analysis of the early stages of meiosis was performed in a 33-year-old man with non-obstructive azoospermia. Newly developed immunocytogenetic techniques were used to identify the synaptonemal complex (SC) in various stages of prophase. antibodies to meiotic proteins identified the SC (SYN1/SCP3), the centromere (CREST) and recombination sites (MLH1). Only 36 meiotic spreads were recovered from the infertile man, compared with hundreds available from controls. One-third of the cells were in zygotene compared with 4% in controls, demonstrating an inability of bivalents to synapse and progress to pachytene. The infertile man had a greatly reduced frequency of recombination, with a mean of only 32.7 MLH1 foci/cell (range 1-60) compared with 46.0 (range 21-62) in control donors. A high proportion of cells (73%) contained at least one autosomal bivalent with zero MLH1 foci, compared with only 4.5% in control donors. Discontinuities in the SC were also more prevalent (68% of cells versus 26% in controls). This is the first demonstration of dramatic pachytene-stage abnormalities in an infertile man using these powerful new immunocytogenetic techniques.
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6/20. Unique t(Y;1)(q12;q12) reciprocal translocation with loss of the heterochromatic region of chromosome 1 in a male with azoospermia due to meiotic arrest: a case report.

    A de novo reciprocal translocation 46,X,t(Y;1)(q12;q12) was found in an azoospermic male with meiotic arrest. cytogenetics and fluorescent in situ hybridization (FISH) were used to define the karyotype, translocation breakpoints and homologue pairing. SRY (Yp), Yq11.2-AZF regions, DAZ gene copies and the distal Yq12 heterochromatin were studied by PCR and restriction analysis using sequence-tagged sites and single nucleotide variants. High resolution GTL, CBL and DA-DAPI staining revealed a (Y;1) translocation in all metaphases and a normal karyotype in the patient's father. FISH showed the presence of the distal Yq12 heterochromatic region in der(1) and loss of the heterochromatic region of chromosome 1. PCR demonstrated the intactness of the y chromosome, including the SRY locus, AZF regions, DAZ genes and distal heterochromatin. A significant decrease (P = 0.005) of Xp/Yp pairing (18.6%), as compared with controls (65.7%), was found in arrested primary spermatocytes, and cell culture and mRNA expression studies confirmed an irreversible arrest at meiosis I, with induction of apoptosis and removal of germ cells by sertoli cells. We characterized a de novo t(Y;1)(q12;q12) balanced reciprocal translocation with loss of the heterochromatic region of chromosome 1, that caused unpairing of sex chromosomes followed by meiosis I arrest, apoptotic degeneration of germ cells and azoospermia.
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7/20. Cytogenetic, molecular and testicular tissue studies in an infertile 45,X male carrying an unbalanced (Y;22) translocation: case report.

    (Y;autosome) translocations have been reported in association with male infertility. Different mechanisms have been suggested to explain the male infertility, such as deletion of the azoospermic factor (AZF) on the long arm of the y chromosome, or meiosis impairment. We describe a new case with a de novo unbalanced translocation t(Y;22) and discuss the genotype-phenotype correlation. A 36 year old male with azoospermia was found to have a mosaic 45,X/46,X, mar karyotype. fluorescence in situ hybridization (FISH) showed the presence of a derivative y chromosome containing the short arm, the centromere and a small proximal part of the long-arm euchromatin of the y chromosome and the long arm of chromosome 22. The unstable small marker chromosome included the short arm and the centromere of chromosome 22. This unbalanced translocation t(Y;22)(q11.2;q11.1) generated the loss of the long arm of the y chromosome involving a large part of AZFb, AZFc and Yq heterochromatin regions. Testicular tissue analyses showed sperm in the wet preparation. Our case shows the importance of documenting (Y;autosome) translocations with molecular and testicular tissue analyses.
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8/20. Meiotic studies in an azoospermic human translocation (Y;1) carrier.

    A reciprocal translocation between the long arm of the y chromosome and the long arm of chromosome 1 was observed in an infertile man with non-obstructive azoospermia. The study was performed using a combination of techniques: immunocytogenetic analysis, which allows the detection of synaptonemal complexes (SCs) and recombination sites (MLH1) simultaneously, and fluorescence in-situ hybridization analysis. Meiotic pairing analysis on 100 pachytene spreads showed the presence of a quadrivalent containing chromosomes 1 and Y. There were many abnormalities in chromosome pairing and recombination. These abnormalities included a great reduction of recombination events (as many as one fifth of the SCs had no MLH1 foci), and high proportions of unpaired regions and discontinuities in the SCs. We discuss the possibility that infertility in this patient may be due to transcriptional repression of part of chromosome 1 involved in the translocation, silencing some genes necessary for the progression of meiosis and causing defective meiotic pairing and recombination.
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9/20. Meiotic arrest at the midpachytene stage in a patient with complete azoospermia factor b deletion of the y chromosome.

    OBJECTIVE: To study the meiosis of a patient with complete azoospermia factor (AZF)b deletion of the y chromosome. DESIGN: Case report. SETTING: La Conception University Hospital, Marseille, france. PATIENT(S): One azoospermic patient. INTERVENTION(S): Yq deletion testing, testicular sperm extraction, and meiotic study with immunocytochemistry. MAIN OUTCOME MEASURE(S): Abnormal synapsis rates in spermatocytes. RESULT(S): We found that most spermatocytes were at an early stage of meiosis. Half of the meiotic germ cells analyzed showed asynapsis, which was mostly extended or total. Discontinuity in the synaptonemal complex was seen in one third of the meiotic cells analyzed. An unusually small number of normal pachytene nuclei were found, all at early pachytene substages. CONCLUSION(S): This is the first demonstration that the synaptic process is impaired in a man with complete deletion of the AZFb interval. Our findings provide evidence that the pachytene checkpoint is situated at the midpachytene substage in humans.
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10/20. Whole-arm translocations between chromosome 1 and acrocentric G chromosomes are associated with a poor prognosis for spermatogenesis: two new cases and review of the literature.

    OBJECTIVE: To analyze unusual translocations involving a chromosome 1 whole arm and an acrocentric G chromosome p arm found in two men with azoospermia. DESIGN: Case report with review of the scientific literature. SETTING: cytogenetics department. PATIENT(S): Two men with azoospermia and normal hormonal levels. INTERVENTIONS(S): Peripheral blood lymphocytes were obtained for karyotype, and metaphases were studied by standard GBG, RBG, and CBG banding procedures. MAIN OUTCOME MEASURE(S): karyotype GBG, RBG, and CBG banding. RESULT(S): karyotype revealed balanced translocation involving a chromosome 1 whole arm and an acrocentric G chromosome p arm: 46,XY,t(1;21)(q11;p13) (patient 1) and 46,XY,t(1;22)(q11;p11) (patient 2). CONCLUSION(S): With regard to published cases of whole-arm translocation of human chromosome 1 with an acrocentric p arm and a maternal origin of these abnormalities, we argue for an impairment of meiosis resulting in a high probability of quadrivalent-XY-body interaction. Male factor infertility might be due to two poor prognostic factors, first the involvement of human chromosome 1 (and its heterochromatic region) and second the involvement of an acrocentric chromosome p-arm breakpoint. This probable interaction between the pachytene quadrivalent and XY body might explain azoospermia.
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