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1/60. 'Identical' twins with discordant karyotypes.

    A chromosomal abnormality in one of the fetuses of a monozygotic twin pregnancy is a rare phenomenon. In the prenatal unit of our cytogenetics laboratory we have recently come across two such heterokaryotypic twin pregnancies. In both cases ultrasound abnormalities were detected in one fetus of each twin pair. Chromosomal analysis showed that one twin pregnancy was discordant for trisomy 21 and the other for 45,X. Ultrasonographic examination suggested a monochorionic twin pregnancy in each case and dna studies confirmed that both sets of twins were monozygotic. Both pregnancies were terminated. Biopsies taken from different sites of the placentas showed chromosomal mosaicism in both cases. There was no clear correlation between the karyotype found close to the site of the umbilical cord insertion in the placenta and the karyotype of the fetus. Sampling of amniotic fluid from both sacs is recommended in diamniotic twin pregnancies if one (or both) of the fetuses has ultrasound abnormalities, even if the twins are apparently monochorionic.
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2/60. 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.
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ranking = 0.90708993654929
keywords = pregnancy, gestation
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3/60. Prenatal ultrasound detection of a congenital epulis in a triple X female fetus: a case report.

    A case of congenital epulis in a triple X infant, whose intra-oral mass was first detected on a 33-week prenatal ultrasound, is described. Two previous ultrasound studies performed at 21 and 28 weeks' gestation showed normal facial anatomy, suggesting accelerated tumour growth during the third trimester. Genetic amniocentesis also showed the infant to possess a 47, XXX karyotype.
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ranking = 0.24042326988263
keywords = gestation
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4/60. Antenatal diagnosis of subependymal heterotopia.

    Subependymal heterotopia consist of gray matter nodules along the lateral ventricular walls and are associated with epilepsy and other cerebral malformations. Some cases have an X-linked inheritance, and early antenatal diagnosis of affected fetuses is important for appropriate management. We present a case of heterotopia diagnosed by sonography and MR imaging at 23 weeks' gestation and discuss the differential diagnosis, reviewing the evolution and imaging appearances of the germinal matrix and its implications for detection of heterotopia.
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keywords = gestation
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5/60. Triploid pregnancy after ICSI of frozen testicular spermatozoa into cryopreserved human oocytes: case report.

    Although freezing oocytes is ethically more acceptable than cryopreservation of embryos, variable oocyte survival, fertilization rate and possible risk of increased ploidy after cryopreservation have precluded the widespread clinical application of oocyte cryopreservation in assisted reproduction techniques. We report a triploid pregnancy from intracytoplasmic sperm injection of recombinant FSH-stimulated frozen/thawed testicular spermatozoa into cryopreserved oocytes in a hormone replacement cycle. To our knowledge, this is the first report of a pregnancy where both gametes have been frozen. It illustrates the need for further research when applying new techniques in assisted reproduction.
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6/60. prenatal diagnosis and genetic analysis of double trisomy 48,XXX, 18.

    prenatal diagnosis of simultaneous occurrence of double trisomy involving chromosomes 18 and X is extremely rare. We report on the prenatal diagnosis, genetic analysis and clinical manifestations of a fetus with both trisomy 18 and trisomy X. A 26-year-old, para 1 woman was referred for genetic counselling at 36 weeks' gestation with the sonographic findings of intrauterine growth retardation (IUGR), polyhydramnios, ventricular septal defect, and an enlarged cisterna magna. Both cordocentesis and amniocentesis revealed a consistent karyotype of 48,XXX, 18. Quantitative fluorescent polymerase chain reaction using polymorphic small tandem repeat markers specific for chromosomes 18 and X rapidly determined that both aneuploidies arose as a result of non-disjunction in maternal meiosis II. Our case shows that two non-disjunction events can occur not only in the same parent, but also in the same cell division. Our case also shows that double trisomy, 48,XXX, 18, can demonstrate an enlarged cisterna magna, IUGR and polyhydramnios in prenatal ultrasound.
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keywords = gestation
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7/60. AZFc deletion detected in a newborn with prenatally diagnosed Yq deletion.

    A case of prenatally diagnosed Yq deletion is described. fluorescence in situ hybridisation (FISH) was used to identify the abnormal chromosome and to exclude mosaicism. Based on the cytogenetic result and the ultrasound investigation the pregnancy was continued. A newborn with normal male genitalia was delivered. Microdeletion analysis of the Yq showed the absence of the AZFc region. This type of deletion has been described as being associated with azoospermia or oligozoospermia with a progressive decrease of sperm number over time. Long-term andrological follow-up of the newborn will be necessary with eventual cryoconservation of sperm at early adulthood. The present report proposes that AZF analysis combined with FISH has an important role in accurate genetic counselling in sex chromosome anomalies.
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keywords = pregnancy
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8/60. First trimester diagnosis of holoprosencephaly and cyclopia with triploidy by transvaginal three-dimensional ultrasonography.

    We present the prenatal three-dimensional (3D) ultrasound findings in a case of holoprosencephaly and cyclopia at 11 weeks gestation. Only holoprosencephaly with missing cyclopia were initially diagnosed because suboptimal views of the fetal face were obtained with transvaginal two-dimensional (2D) ultrasonography due to fetal position. chromosomes identified by analysis of a fluid sample from early amniocentesis demonstrated a triploidy (69, XXX), spontaneous fetal demise occurred at 12 weeks and the pregnancy was terminated. This case demonstrated the usefulness of transvaginal 3D ultrasonography in establishing the final diagnosis.
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ranking = 0.57375660321596
keywords = pregnancy, gestation
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9/60. sex chromosome mosaicism in gonads of a fetus with cystic hygroma and deletion of the short arm of y chromosome including loss of SRY.

    The SRY gene on the short arm of the y chromosome is necessary for male development. Without SRY, patients with 46,XY karyotype develop as females, fail to achieve normal puberty and have dysgenic gonads and a high incidence of gonadoblastoma. Here we report a female fetus, aborted at 17 weeks of pregnancy, with a non-mosaic 46,X,del(Y)(p11.2).ish del(Y)(SRY-) karyotype diagnosed by classical cytogenetics and fluorescence in situ hybridization (FISH). Ovarian tissue was full of oocytes and mitotic figures. FISH studies of ovarian tissues with X and Y centromere probes revealed extensive sex chromosome mosaicism, manifested by loss of the y chromosome and polysomy of the x chromosome. We propose that x chromosome polysomy is a post-zygotic event that arises to facilitate gonadal differentiation in the absence of all factors necessary for normal gonadal development.
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keywords = pregnancy
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10/60. Clinical, cytogenetic, and molecular findings in 45,X/47,XX, 18 mosaicism: clinical report and review of the literature.

    We report cytogenetic and molecular findings performed in a patient with double mosaic aneuploidy. Chromosome analysis of amniotic fluid cells from a 17-week-old fetus was performed because of advanced maternal age. Two karyotypes were detected: 45,X and 47,XX, 18 (50:50%). The same cell lines were determined in uncultured and cultured amniocytes of a second amniotic fluid sample, in fetal lymphocytes, and in uncultured and cultured cells of achilles tendon by conventional cytogenetics and fluorescence in situ hybridization (FISH). In the different investigated tissues, the percentage of cells with 45,X karyotype ranged from 20-99% and the percentage of cells with 47,XX, 18 ranged from 1-80%. The pregnancy was terminated at 22 0 weeks because of a severe cardiac malformation. Pathologic examination showed a fetus with aspects typical for manifestation of trisomy 18 and monosomy X, especially in the internal organs. The parent and cell stage of origin was determined by short tandem repeat typing and revealed a maternal meiotic division error that led to trisomy 18, as well as a somatic loss of a paternal sex chromosome. Only two other patients with the same mosaicism have been reported so far. genetic counseling and prognosis remains challenging.
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keywords = pregnancy
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