An article published in Nature describes how the first use of precision editing has shed light on a gene essential for embryonic development. The authors caution that the clinical application of genome editing in human embryos requires rigorous ethical analysis and oversight, as well as broad public debate and support.
A systematic review with a meta-analysis published in The Lancet Obstetrics, Gynecology, & Women’s Health concludes that there is insufficient evidence that most complementary treatments for in vitro fertilization (IVF) improve fertility in patients undergoing this procedure. Some of these techniques involve introducing platelet-rich plasma into the uterus or ovaries, administering a lipid infusion into the bloodstream, administering corticosteroids, or performing preimplantation genetic testing to detect aneuploidies—that is, abnormalities in chromosome number. According to the study, which included 85 clinical trials, there is only evidence—albeit of low quality—suggesting a possible benefit from three treatments: EmbryoGlue—a method of embryo transfer containing hyaluronic acid—endometrial scraping, and physiological intracytoplasmic sperm injection—a technique for selecting sperm.
A team led by the University of Cambridge (UK) has used human stem cells to produce three-dimensional embryo-like structures that replicate certain aspects of early development, including, they say, the production of blood stem cells. They have called these structures “hematoids” and, according to the university press release, “they offer great potential for better understanding blood formation during the earliest stages of human development, for simulating disorders such as leukemia, and for producing long-lived blood stem cells for transplantation.” The results are published in the journal Cell Reports.
A team of researchers has used embryonic stem cell engineering to create a bipaternal mouse - a mouse with two male parents - that lived to adulthood. Their results, published in the journal Cell Stem Cell, show how targeting a particular set of genes involved in reproduction enabled this breakthrough in unisexual reproduction in mammals.
A new technique developed at the Institut de Bioenginyeria de Catalunya (IBEC) has succeeded in assessing the health of mouse oocytes and embryos in a non-invasive way, according to a study published in PNAS. The method generates 3D images to visualise the metabolism of oocytes and embryos obtained by in vitro fertilisation and makes it possible to select those that are most likely to implant and develop, say the authors.
A multidisciplinary team of researchers has succeeded in developing different types of organoids from cells obtained from amniotic fluid. According to the authors, this breakthrough could help to better understand the later stages of development during pregnancy and to advance research into congenital anomalies. The study is published in the journal Nature Medicine.
A team of Chinese researchers report today in the journal Nature Communications the successful cloning of a rhesus monkey, with a healthy placenta, which survived for more than two years. According to the authors, this could improve the efficiency of the monkey cloning process, which so far is very low. Previously, different teams have cloned more mammalian species, including 'Dolly the sheep' and another species of macaque (Macaca fascicularis).
A Chinese research team has reported the birth of a crab-eating macaque that is a chimera: an animal generated from the mixing of embryonic cells from two different individuals; in this case, from the same species, according to the journal Cell. Until now, this type of chimera had only been developed with rodents. This is the first time it has been achieved in non-human primates.
Scientists have successfully developed pig embryos whose kidneys contain 50-60% human cells. Gestation was terminated at 25-28 days, and the organ structure was normal. According to the press release accompanying the article, "this is the first time that a solid humanised organ has been grown inside another species, although previous studies have used similar methods to generate human tissues". The results are published in the journal Cell Stem Cell.
Berna Sozen's lab at Yale University has announced a new milestone in the competition to create synthetic embryos: their human pluripotent stem cells self-organise into structures that mimic embryonic development on days 9-14 after fertilisation and include extra-embryonic tissues. Their achievement is published in Nature at the same time as another similar study, that of Magdalena Zernicka-Goetz, who a fortnight ago previewed her stem cell-derived human embryo model to The Guardian, sparking a controversy with Jacob Hanna, author of a preprint showing that she had achieved true synthetic embryos.