1/133. Secondary infertility as early symptom in a man with multiple endocrine neoplasia-type 1.multiple endocrine neoplasia-type 1 (MEN1) is an autosomal dominant familial cancer syndrome characterized by parathyroid hyperplasia, pancreatic endocrine tumours and pituitary adenomas. Here, we report a patient with a history of insulinoma who developed secondary infertility as a further symptom of the disease. When he was first examined at the age of 36 years, he complained of weakness, reduced libido and impotence. Laboratory evaluation revealed non-obstructive azoospermia and hyperprolactinaemia. In contrast to sexual activity and serum prolactin, semen quality did not significantly respond to bromocriptine therapy. During follow-up, a growing pituitary adenoma caused acromegaly with elevated serum concentrations of growth hormone, insulin-like growth factor 1 (IGF-1), and prolactin. After microsurgery of the tumour at the age of 44 years, sperm concentration persistently increased up to 5.6 x 10(6)/ml. In accordance with the clinical diagnosis of MEN1, dna sequencing revealed a mutation in exon 2 of the menin gene which results in a truncated, inactive protein product. In conclusion, MEN1 with pituitary lesions may cause severe hypogonadism and infertility. Both hyperprolactinaemia and overproduction of growth hormone and IGF-1 seem to be involved in testicular dysfunction in the present case. The possible role of menin in the testis, however, remains to be elucidated.- - - - - - - - - - ranking = 1keywords = sex (Clic here for more details about this article) |
2/133. Three-generation evaluation of Y-chromosome microdeletion.Sperm cells can be retrieved directly from the testis (testicular sperm extraction [TESE] procedure) and used for intracytoplasmic sperm injection (ICSI), circumventing underlying spermatogenetic defects. Thus, it is important that added information be available on the genetic defects in men undergoing TESE for the ICSI procedure and on the transmission of genetic factors associated with infertility to the offspring. We report a three-generation genetic analysis of a family with a case of male factor infertility. The proband, previously diagnosed as infertile, was physically examined and laboratory tested for gonadotrophic hormones, semen analysis, karyotype and Y-chromosome microdeletion screening in the blood and testis. The Y-chromosome microdeletion screening was performed by multiplex polymerase chain reaction with 20 Y-chromosome sequenced, tagged sites located at the y chromosome. A microdeletion including the AZF-c region was detected in the azoospermic patient. His father, four brothers, and three offspring born after ICSI also underwent Y-chromosome microdeletion screening. The genetic analysis of the male members of the patient's family did not reveal similar microdeletions. The newborn male was found to bear a Y-chromosome microdeletion similar to that of his father. The fertilization capacity of the proband testicular microdeleted spermatozoa by the ICSI procedure is described. The transfer of the genetic defect raises the possibility that the son will have the same fertility problem as his father.- - - - - - - - - - ranking = 591.10937313008keywords = chromosome (Clic here for more details about this article) |
3/133. Men with infertility caused by AZFc deletion can produce sons by intracytoplasmic sperm injection, but are likely to transmit the deletion and infertility.Deletion of the AZFc region of the y chromosome is the most frequent molecularly defined cause of spermatogenic failure. We report three unrelated men in whom azoospermia or severe oligozoospermia was caused by de-novo AZFc deletions, and who produced sons by intracytoplasmic sperm injection (ICSI). We employed polymerase chain reaction (PCR) assays to examine the Y chromosomes of their four infant sons. All four sons were found to have inherited the y chromosome deletions. Such sons are likely to be infertile as adults. This likelihood should be taken into account when counselling couples considering ICSI to circumvent infertility due to severe oligozoospermia or non-obstructive azoospermia.- - - - - - - - - - ranking = 177.33281193902keywords = chromosome (Clic here for more details about this article) |
4/133. Deletion of y chromosome involving the DAZ (deleted in azoospermia) gene in XX males.The testicular histology and the presence or absence of 32 Y dna loci was investigated, with a focus on the long arm of y chromosome (Yq) interval 6, by means of a polymerase chain reaction strategy in 2 XX males. seminiferous tubules lined by only sertoli cells and a slight thickening of tubular walls were observed. The men showed an absence of 32 Y dna loci. These facts suggest that severe spermatogenic impairment is caused by deletions of Yq interval 6 in XX males.- - - - - - - - - - ranking = 295.55468656504keywords = chromosome (Clic here for more details about this article) |
5/133. 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 = 6048.5375086594keywords = sex chromosome, chromosome, sex (Clic here for more details about this article) |
6/133. 45,X/46,X,r(Y) karyotype transmitted by father to son after intracytoplasmic sperm injection for oligospermia. A case report.BACKGROUND: The advent of assisted reproductive techniques, such as intracytoplasmic sperm injection (ICSI), has permitted conception and successful pregnancy for an increasing population of infertile men. Approximately 13.7% of infertile men with aspermia and 4.6% with oligospermia have a coexistent chromosome abnormality. Although the ICSI procedure appears safe thus far, early studies are in progress to evaluate outcomes of such pregnancies. For men whose infertility is linked to genetic conditions, it is an unprecedented challenge to predict the potential effects on their offspring. CASE: At 18 weeks' gestation, a 45,X/46,X,r(Y) karyotype was found on genetic amniocentesis performed for advanced maternal age. The pregnancy was achieved by ICSI using sperm from the husband, who was infertile due to severe oligospermia. Subsequently the same karyotype was found in the father. To our knowledge, this is the first reported case of familial transmission of ring y chromosome. CONCLUSION: It is strongly recommended that ICSI and other new assisted reproductive techniques be preceded by genetic screening for male infertility as well as other indications warranted by the family history since traditional risk assessment may require revision and outcomes may be uncertain in some cases.- - - - - - - - - - ranking = 132.52178269214keywords = chromosome, chromosome abnormality (Clic here for more details about this article) |
7/133. A new point mutation of the androgen receptor gene in a patient with partial androgen resistance and severe oligozoospermia.Mutations of the androgen receptor gene in genetic males cause a variety of androgen insensitivity syndromes varying from female phenotype through intersexuality to male phenotype with infertility. The identification of a missense mutation in the steroid-binding domain in an infertile male with mild features of androgen insensitivity is reported here.- - - - - - - - - - ranking = 1keywords = sex (Clic here for more details about this article) |
8/133. y chromosome microdeletion in a father and his four infertile sons.Microdeletions of Yq are associated with azoospermia and severe oligozoospermia. In general, men with deletions are infertile and therefore deletions are not transmitted to sons unless in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) are performed. We report an unusual family characterized by multiple members with infertility and Yq microdeletion. Complete reproductive history, semen analyses and blood samples were elicited from relevant family members. dna preparation and quantification were performed using commercial kits. A total of 27 pairs of sequence tagged sites based primer sets specific for the Y microdeletion region loci were used for screening. Southern blots using deleted in azoospermia (DAZ) and ribosomal binding motif (RBM) cDNAs were then analysed for confirmation. The proband, his three brothers and father were all found to be deleted for DAZ but not RBM. At the time of analysis, the proband's father was azoospermic whereas his four sons were either severely oligozoospermic or azoospermic. Unlike their father, the four sons are infertile and have no offspring, except for one of them who achieved a daughter only after IVF/ICSI treatment for infertility. Microdeletions of Yq involving the DAZ gene are associated with a variable phenotypic expression that can include evidently normal fertility.- - - - - - - - - - ranking = 236.44374925203keywords = chromosome (Clic here for more details about this article) |
9/133. An azoospermic man with a de novo point mutation in the Y-chromosomal gene USP9Y.In humans, deletion of any one of three Y-chromosomal regions- AZFa, AZFb or AZFc-disrupts spermatogenesis, causing infertility in otherwise healthy men. Although candidate genes have been identified in all three regions, no case of spermatogenic failure has been traced to a point mutation in a Y-linked gene, or to a deletion of a single Y-linked gene. We sequenced the AZFa region of the y chromosome and identified two functional genes previously described: USP9Y (also known as DFFRY) and DBY (refs 7,8). Screening of the two genes in 576 infertile and 96 fertile men revealed several sequence variants, most of which appear to be heritable and of little functional consequence. We found one de novo mutation in USP9Y: a 4-bp deletion in a splice-donor site, causing an exon to be skipped and protein truncation. This mutation was present in a man with nonobstructive azoospermia (that is, no sperm was detected in semen), but absent in his fertile brother, suggesting that the USP9Y mutation caused spermatogenic failure. We also identified a single-gene deletion associated with spermatogenic failure, again involving USP9Y, by re-analysing a published study.- - - - - - - - - - ranking = 59.110937313008keywords = chromosome (Clic here for more details about this article) |
10/133. Neocentromere formation in a stable ring 1p32-p36.1 chromosome.Neocentromeres are functional centromeres formed in chromosome regions outside the normal centromere domains and are found in an increasing number of mitotically stable human marker chromosomes in both neoplastic and non-neoplastic cells. We describe here the formation of a neocentromere in a previously undescribed chromosomal region at 1p32-->p36.1 in an oligospermic patient. Cytogenetic GTL banding analysis and the absence of detectable fluorescence in situ hybridisation (FISH) signals using telomeric probes indicate the marker to be a ring chromosome. The chromosome is negative for CBG banding and is devoid of detectable centromeric alpha satellite and its associated centromere protein CENP-B, suggesting activation of a neocentromere within the 1p32-36.1 region. Functional activity of the neocentromere is shown by the retention of the ring chromosome in 97% of the patient's lymphocytes and 100% of his cultured fibroblasts, as well as by the presence of key centromere binding proteins CENP-E, CENP-F, and INCENP. These results indicate that in addition to CENP-A, CENP-C, and CENP-E described in earlier studies, neocentromere activity can further be defined by CENP-F and INCENP binding. Our evidence suggests that neocentromere formation constitutes a viable mechanism for the mitotic stabilisation of acentric ring chromosomes.- - - - - - - - - - ranking = 591.10937313008keywords = chromosome (Clic here for more details about this article) |
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