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Alicante, Spain

Lledo B.,IB Biotech. | Guerrero J.,Instituto Bernabeu of Fertility and Gynecology | Ortiz J.A.,IB Biotech. | Morales R.,IB Biotech. | And 5 more authors.
Human Reproduction

BACKGROUND: Fragile X syndrome is associated with low ovarian reserve and poor ovarian response. The aim of this study was to investigate whether CGG repeats on the fragile X mental retardation 1 (FMR1) gene have predictive value for ovarian response to stimulation with gonadotrophins and for clinical outcome in our oocyte donation program. METHODS: Oocyte donor candidates were selected according to Instituto Bernabeu oocyte donation program requirements. Fragile X genetic screening was performed in 204 oocyte donors, defining 141 controls and 63 cases: 35-39 repeats (n = 34), 40-45 (n = 12) and >45 (n = 17). All the patients underwent ovarian stimulation using a GnRH antagonist protocol and received a GnRH agonist trigger. The main factors used to measure outcome were oocyte yields, days of stimulation, gonadotrophin dosages, biochemical pregnancy, ongoing pregnancy and miscarriage rates. RESULTS: No differences between the study group and controls were reported in oocyte yields (17.5 versus 18.9) or days of stimulation (11.40 versus 9.82). The control group used significantly more gonadotrophin (2212 versus1850 IU) than the study group. Clinical outcome was not affected by the CGG repeats on the FMR1 gene in oocyte donors. CONCLUSIONS: No negative effect was observed for intermediate-sized CGG repeats on ovarian stimulation and clinical outcome using a non-confounding model of oocyte donation. These results disagree with previous studies performed on infertility patients. Owing to the present study, fragile X genetic screening should not be considered for prediction of response to ovarian stimulation. © The Author 2011. Published by Oxford University Press. All rights reserved. Source

Lledo B.,IB Biotech. | Ortiz J.A.,IB Biotech. | Morales R.,IB Biotech. | Manchon I.,Instituto Bernabeu of Fertility and Gynecology | And 3 more authors.
Human Fertility

Complex chromosomal rearrangements (CCRs) are structural aberrations involving more than two chromosomes which rarely appear in individuals with normal phenotypes. These individuals report fertility problems, recurrent miscarriages, or congenital anomalies in newborn offspring as a consequence of either meiotic failure or imbalanced chromosome segregation. A CCR involving chromosomes 5, 15, and 18 was discovered in a phenotypically normal man through a fetus with congenital malformations and partial trisomy of chromosome 15 and monosomy of chromosome 5. Ultrasound examination at 20 weeks of gestation showed severe oligoamnios and hydrothorax. Prenatal cytogenetic analysis and array comparative genomic hybridization (array-CGH) revealed a female fetus with dup15q26.3 and del5p15.33. We diagnosed the CCR using three-color fluorescence in situ hybridization (three-color FISH), and a balanced CCR using array-CGH and FISH was diagnosed in the paternal karyotype. The father is a carrier of a balanced translocation 46,XY,t(5;15;18)(p15.31;q26.3;p11.2). Due to the complexity of these rearrangements the diagnosis is difficult and the reproductive outcome uncertain. Reporting such rare cases is important to enable such information to be used for genetic counseling in similar situations and help estimate the risk of miscarriage or of newborns with congenital abnormalities. © 2013 The British Fertility Society. Source

Lledo B.,IB Biotech. | Ortiz J.A.,IB Biotech. | Morales R.,IB Biotech. | Ten J.,Instituto Bernabeu of Fertility and Gynaecology | And 2 more authors.
Human Reproduction

Background: Human translocation carriers may present alterations in meiosis. Understanding the mechanism of meiotic segregation of reciprocal translocations is important for estimation of the risk of either pregnancy loss or birth defects. The objective of this work was to estimate meiotic segregation rates in preimplantation embryos from preimplantation genetic diagnosis (PGD) cycles of female and male reciprocal translocation carriers. Methods: In 20 cycles for 14 couples, PGD was performed on 118 day three embryos using fluorescence in situ hybridization (FISH) with specific probes for each translocation. The meiotic segregation modes and the effect of the paternal origin of translocated carrier were estimated. Results: Overall, the proportions of alternate segregation for normal or balanced chromosome contents in preimplantation embryos from PGD cycles in reciprocal male and female carriers were not significantly different (35.5 versus 23.8). However, the frequencies of adjacent-1 and adjacent-2 segregation were lower in embryos from female reciprocal translocation carriers than from male carriers. For male translocations, alternate segregation was the most frequent mode. The proportion of 3:1 segregation was the most frequent in female translocations carriers. Conclusion: SWe report differences in segregation modes in embryos obtained from PGD cycles according to the gender of reciprocal translocation carrier. However, these differences did not affect the proportion of balanced embryos and the take home baby rate. The analysis of the meiotic behaviour of chromosomes and the differences between the meiotic products of female and male for a chromosomal rearrangement could help predict the outcome of PGD for translocation carriers. © 2010 The Author. Source

Lledo B.,IB Biotech. | Llacer J.,Instituto Bernabeu of Fertility and Gynecology | Turienzo A.,IB Biotech. | Ortiz J.A.,IB Biotech. | And 5 more authors.
Reproductive BioMedicine Online

The human androgen receptor (AR) gene contains a highly polymorphic CAG repeat sequence within exon 1. In-vitro studies have shown a relationship between CAG repeats in the AR gene and its transactivation potential. This variation in length may play a role in anovulatory infertility. The objective of this study was to investigate whether CAG polymorphism of the AR gene has a predictive value for ovarian reserve, response and cycle outcome in an egg donor programme. CAG length of the AR gene was determined in 147 oocyte donors. All donors underwent ovarian stimulation with a gonadotrophin-releasing hormone antagonist protocol (n = 355). No differences were reported in days of stimulation, gonadotrophin doses, and number of oocytes retrieved. Clinical outcomes were not affected by the CAG repeat length of the AR gene; the primary end-point, antral follicle count, was significantly affected (P < 0.05). In conclusion, in a population of fertile egg donors AR gene CAG polymorphism does not affect ovarian response to gonadotrophins. Antral follicle count was associated with the CAG polymorphism genotype. This suggests that genetic factors may increase susceptibility to poor ovarian reserve, and that AR gene genotype could play a role in the natural ovarian ageing process. © 2014 Reproductive Healthcare Ltd. All rights reserved. Source

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