Lluís Montoliu

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. 

The latest episode of competition between research groups working on the same topic, a very common situation in science, should not distract us from the actual achievement: synthetic human embryos, in the laboratory, made from stem cells, up to a post-implantation stage. Now, we must decide what status or condition we will grant to these synthetic embryos. Once again, science is leaping forward and testing the limits of the laws, posing new ethical challenges for us to solve. 

Chinese researchers have succeeded in developing macaque embryo-like structures from embryonic stem cells. They have also managed to implant them in the uterus of female macaque monkeys and develop a hormonal response similar to that of a gestation, although they have only survived for about a week. According to the authors, whose research is published in Cell Stem Cell, these models could be used to improve our understanding of embryonic development and to investigate the causes of some early miscarriages.

In January 2013, two laboratories demonstrated that CRISPR tools could be used to edit genes in human cells. Ten years later, the first patients are already benefiting from the molecular scissors to overcome incurable diseases. This week in Science, one of the pioneers of CRISPR, Nobel laureate Jennifer Doudna, summarises the history of these tools, without forgetting that it all began thirty years ago with the findings of Francis Mojica in the Santa Pola salt flats.

Ischaemia-reperfusion injury is one of the causes of damage caused by diseases such as myocardial infarction. A study published in the journal Science has used base editors, a gene-editing tool derived from CRISPR, to modify a key protein in the hearts of mice. According to the authors, the intervention allowed them to recover their function after a heart attack and could potentially be used in a wide range of patients, as it does not depend on the presence of a specific mutation.

A team of researchers from the Health Institute Carlos III has published an article quantifying the diagnostic delay of rare diseases in Spain with data from the period 1960-2021. The study reveals that more than half of the patients experienced a delay in diagnosis, that the average delay exceeds six years, and that both the percentage of those affected by the delay and the average time have decreased over the years.

A US team has successfully integrated brain-like tissue derived from human stem cells into the brains of newborn rats. The research is published in the journal Nature.

The extraordinary plenary session of the Congress of Deputies today approved the reform of the Law on Science, Technology and Innovation. After being passed in the Lower House without any votes against it on 23 June, the bill was approved in the Senate on 20 July with an amendment referring to indefinite-term contracts, which was rejected today in Congress. 

Research published in Nature shows the creation of synthetic mouse embryos derived from stem cells. The embryo model copies the stages of natural rodent embryo development that take place up to day 8.5 after fertilisation and includes regions of the brain, a neural tube and a structure similar to a beating heart.