1/3. 47,XX mar karyotype containing genes from the azoospermia factor region. A case report.BACKGROUND: Abnormal embryo development is the major cause of implantation failure and accounts for the low rate of human fertility in vitro and in vivo. Chromosome abnormalities are widely involved in this process through meiotic nondisjunction, fertilization abnormalities and mitotic nondisjunction. CASE: In our assisted reproductive technology program a couple underwent cytogenetic analysis. The woman had a 47,XX mar karyotype. We investigated this patient by chromosome analysis, fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) dna analysis. The marker chromosome was found to be very similar to a y chromosome in size and QFQ staining pattern. Therefore, it was tested by FISH using alpha- and beta-satellite dna specific for the y chromosome, some YACs specific for the long arm of the y chromosome and alpha-satellite dna specific for 15 chromosomes as probes. In order to define this marker, the next step was PCR amplification of the whole genomic dna using specific landmarks (sequence-tagged sites) to encompass the azoospermia factor (AZF) region on the long arm of the y chromosome. CONCLUSION: A woman had an extra chromosome containing centromeric dna derived from the Y and 15 other chromosomes, heterochromatic regions derived from 15 chromosomes and a large heterochromatic block at the end of the long arm that definitely was not y chromosome heterochromatin (beta-satellite). PCR showed several genes of the y chromosome long arm that are assumed to be involved in male gametogenesis. Phenotypic effects could not be excluded because of the presence of AZF genes. Oocyte karyotyping might better explain the role of the genetic problem on female infertility.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/3. Swyer syndrome with SRY y chromosome and rudimentary internal genitalia demonstrating temporary action of antimullerian hormone in utero: a case report.BACKGROUND: XY gonadal dysgenesis is characterized by streak gonads in phenotypic females without somatic abnormalities. This case demonstrated a hypoplastic uterus, an unlikely finding for the syndrome, suggesting insufficient function of antimullerian hormone prenatally. CASE: A 20-year-old, female virgin was first seen 2 years earlier complaining of primary amenorrhea. She was 168 cm tall, and secondary sexual characteristics, such as breast development and pubic and axillary hair, were absent on physical examination. Chromosome analysis with fluorescence in situ hybridization revealed 46,XY, and a molecular investigation was undertaken to assess the possibility of a mutation in SRY through dna sequencing. SRY mutations were absent. Bilateral laparoscopic removal of dysgenetic gonads was performed at another medical center immediately after genetic confirmation for an increased risk of malignancy. When the patient was seen 1 year later, we performed ultrasonography because of no menstrual outflow. Pelvic ultrasonography revealed a hypoplastic uterus (26 x 12 mm) with a rudimentary cervix. CONCLUSION: Clinical phenotypes of different mutations of the y chromosome, particularly on SRY, may cause Swyer syndrome patients to have a uterus with fertility potential after oocyte donation.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/3. infertility in carriers of two bisatellited marker chromosomes.Two unrelated sterile patients, a male and a female, with karyotypes characterized by the presence of two supernumerary bisatellited marker chromosomes, were studied with the aid of fluorescence in situ hybridization (FISH). Using alphoid centromeric specific probes, the markers were identified as an idic (15) (pter-q11) and a mar (14). In both cases a single accessory bisatellited marker was present in the karyotype of one of the parents. A possible correlation between the excess of constitutive heterochromatin and meiotic disturbances in the two patients is discussed.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |