1/4. Birth of healthy children after preimplantation diagnosis of beta-thalassemia by whole-genome amplification.Preimplantation genetic diagnosis (PGD) offers couples at risk for transmitting an inherited disorder the possibility to avoid the need to terminate affected pregnancies. PGD for monogenic diseases is most commonly accomplished by blastomere biopsy from cleavage-stage embryos, followed by PCR-based dna analysis. However, the molecular heterogeneity of many monogenic diseases requires a diagnostic strategy capable of detecting a range of mutations and compound genotypes. With the above considerations, we developed an accurate and reliable strategy for analysis of beta-globin gene mutations, applicable for PGD for the wide spectrum of beta-thalassemia major mutations in the Chinese population. The strategy involves primer-extension preamplification (PEP), followed by nested PCR and reverse dot blot (RDB) for mutation detection since it facilitates simultaneous analysis of more than one mutation in a single cell. This report describes the application of the strategy in two clinical IVF/PGD cycles at risk for transmitting beta-thalassemia major, which resulted in the first thalassemia-free children born after PGD in china.- - - - - - - - - - ranking = 1keywords = preimplantation, embryo (Clic here for more details about this article) |
2/4. Birth of a healthy infant following trophectoderm biopsy from blastocysts for PGD of beta-thalassaemia major.PGD is a well accepted reproductive choice for couples at genetic risk and involves the diagnosis and transfer of unaffected IVF embryos. PGD for monogenetic diseases is most commonly accomplished by the biopsy of one or two blastomeres from cleavage stage embryos, followed by PCR-based protocols. However, PCR-based dna analysis of one or two cells is subject to several problems, including total PCR failure, or failure of one allele to amplify. Trophectoderm biopsy at the blastocyst stage enables the removal of more than two cells for diagnosis while being non-invasive to the inner cell mass which is destined for fetal development. The aim of this study was to develop a safe, reliable technique for the biopsy of trophectoderm cells from human blastocysts. This case report demonstrates that removal of trophectoderm cells prior to blastocyst transfer is compatible with implantation and development to term. Here we report successful PGD for beta-thalassaemia following trophectoderm cell biopsy from blastocysts and the birth of a healthy infant.- - - - - - - - - - ranking = 0.0032207350474554keywords = embryo (Clic here for more details about this article) |
3/4. Transfusion-dependent homozygous beta-thalassaemia major: successful twin pregnancy following in-vitro fertilization and tubal embryo transfer.Homozygous beta-thalassaemia (thalassaemia major) is a severe, transfusion-dependent anaemia that also causes infertility due to endocrine impairment. Very few pregnancies are reported among such patients and there is only one report in the literature referring to a pregnancy achieved with ovulation induction and intra-uterine insemination. We report here the first successful twin pregnancy following in-vitro fertilization and tubal embryo transfer in a transfusion-dependent homozygous beta-thalassaemic woman with an oligoasthenozoospermic partner. Prior to ovarian stimulation, desferrioxamine was discontinued due to potential fetotoxicity. Pre-gestational transfusional and chelating therapies were resumed after delivery. In such patients, ovulation induction and assisted reproductive techniques appear crucial in achieving pregnancy with concurrent haematological balance without desferrioxamine administration.- - - - - - - - - - ranking = 0.0080518376186384keywords = embryo (Clic here for more details about this article) |
4/4. Defective oocytes as a possible cause of infertility in a beta-thalassaemia major patient.Impaired reproduction is common among patients afflicted with beta-thalassaemia major and is attributed mainly to the deposition of haemosiderin in the pituitary gland and ovaries. In-vitro fertilization (IVF)--embryo transfer cycles including ovum donation cycles are described for the first time in a patient with beta-thalassaemia major. The patient's oocytes were not fertilized by the husband's sperm in repeated IVF attempts. However, when donated oocytes were used, in two consecutive cycles, most were fertilized by the husband, yielding pregnancies after each embryo transfer. It is suggested that in this case of beta-thalassaemia major, impaired oocyte function contributed to infertility. However, a possible association between thalassaemia major and defective oocytes should be tested on a basis of additional IVF-embryo transfer cycles in these patients.- - - - - - - - - - ranking = 0.0048311025711831keywords = embryo (Clic here for more details about this article) |