They say that Archimedes, the great Greek engineer and physicist from Syracuse, said: “Give me a place to stand and I will move the world.” Although he was referring to the law of the lever, the image it generates in our brain is so powerful that we metaphorically refer to it in many other human situations where a problem needs to be solved that could be approached with the right data and tools. This is how we scientists who dedicated ourselves to human genetics felt during the 90s, in the full effervescence of the Human Genome Project. This year we celebrate the 25th anniversary of the publication of the first complete draft of the human genome, the instruction manual that explains what humans are like and which marked a before and after for biomedicine.

When supercentenarians are asked what their secret to a long life is, some claim it's having a life purpose, the famous ikigai of the Japanese; while others, more pragmatic, maintain that the recipe for longevity involves a daily yogurt. Until now, the science of aging had indicated that, to reach centenarian status, it was necessary to follow a healthy lifestyle: healthy food, no smoking or alcohol, exercise, rest, and stress under control. But now a new work published in Science It puts another factor ahead of all this: our genetic inheritance.

In 1975, following a conference on recombinant DNA in Asilomar, California, a moratorium—self-imposed and widely accepted by experts—came into effect to allow time to assess the risks of the new technology, which for the first time allowed the mixing of genetic material from different species, thus creating modified organisms. The potential applications were fabulous, as was the possibility of generating unimaginable disasters. It was necessary to carefully consider the consequences of using the knowledge that had been acquired and to agree on minimum regulations that everyone could follow.

Nearly 200 babies have been conceived in Europe over the past decade using sperm from a donor carrying a potentially deadly cancer gene. Of these, a dozen were born in Spain, according to an investigation by the European Broadcasting Union's (EBU) Investigative Journalism Network published Wednesday. The man donated his sperm at the Copenhagen headquarters of the European Sperm Bank (ESB) in 2005 after passing all the required medical examinations at the time. The Danish bank then sold the sperm to various clinics across Europe, including three in Spain. The donor, identified as 7069 or Kjled, is a student who donated sperm a decade ago and carries a genetic mutation that increases the risk of developing cancer. His sperm was sold between 2006 and 2023 to 67 fertility clinics across Europe, despite some countries limiting the number of births per donor, as there is no international regulation governing this, according to an investigation by several European media outlets, including RTVE. Thirty-five children were conceived in Spain using his sperm, but only ten were born alive. In 2023, the use of this sperm was blocked after a sample was found to contain a "new and potentially fatal genetic alteration," a pathology derived from the TP53 mutation, which is Li-Fraumeni syndrome, a disease that predisposes the carrier to complications. RTVE Ann-Kathrin Klym, head of the laboratory at the Berliner Samenbank sperm bank, explained that in Spain, once the alert was received, clinics immediately blocked the samples they had received to prevent further use.

Why do some women only have girls or only boys? This is a question many people ask when they observe that some families with three or four children all have the same biological sex. Is there a genetic factor that determines this? In human populations as a whole, if no external discriminatory factor is at play—such as sex selection at birth or wars, among others— The ratio of biological male to female sex is very close to 1:1Certainly, there is a slight increase in the percentage of boys compared to girls among newborns, but after one year of life, these percentages are already equivalent. The fact that humans have few offspring makes it difficult to analyze whether there is any genetic factor skewing the proportion when we are only looking at the progeny of a single couple. With two or three children, statistically it is difficult to distinguish the action of chance from the action of some genetic or environmental factor, which must be subtle.

Evolution is a slow and gradual process through which species accumulate small changes over time, and only the individuals best adapted to a specific environment are able to survive and pass on their genetics to future generations. This is the theory developed by Charles Darwin in 1859. But the British naturalist could not explain why there are no fossil records of those intermediate forms that allow us to see the gradual evolution of species. This scarcity of samples led paleontologists Stephen Jay Gould and Niles Eldredge to propose that species do not change slowly, but rather remain stable for millions of years and suddenly make brief and radical evolutionary leaps. This is known as the theory of punctuated equilibrium, and now a study led by the Institute of Evolutionary Biology (IBE) has reached conclusions that support it and, therefore, challenge the Darwinian system.

What determines whether a mammal is male or female? Until now, science has only had one answer: genetics. For example, metabolic factors. Specifically, iron deficiency in the mother during pregnancy can profoundly affect some mouse offspring and eventually cause sex reversal. programmed A mouse that has no testicles may end up developing ovaries for a seemingly trivial reason. Researchers reproduced a deficient iron concentration—around 60% below normal levels—in female mice that were, a priori, pregnant with males, and observed that 6 of the 39 offspring were born with ovaries. Led by Makoto Tachibana of Osaka University, the research It was published this Wednesday in the magazine Nature and represents a first step in investigating the effects of iron deficiency on human pregnancies.

One of the news stories of the month is the publication in the media of a story about plush-like mice with fluffy, golden fur, with an enticing headline about the resurrection of mammoth genes. These mice were created by a privately held biotechnology company, Colossal, which aims to de-extinct species, has set its sights on the mammoth. Aside from the obvious appeal to potential investors, why the mammoth and not any other species? According to the company, They intend to contribute to repopulating the Arctic tundra with mammoths., and solve the problem of the release of CO₂ by permafrost, which would contribute to combating climate change.

Significant advance in the understanding of human genetics. An international team of scientists, including Dr. Àlex Bayés of the Sant Pau Research Institute (IR Sant Pau) in Barcelona, ​​​​published this Thursday in the magazine Nature the most comprehensive manual to date on the functioning of the human genome. The study identified more than 68,000 functions, corresponding to 82% of all genes.

A team of scientists led by the Spaniard Juan Carlos Izpisua, from the Stalk Institute in the United States, and the Chinese Ji Weizhi, from Kunming University, have created monkey embryos containing human cells. Of the 132 embryos created, three have survived 19 days in the laboratory and have come to form spherical structures of about ten thousand cells, at which point the scientists have stopped development. The work, published in the journal Cell has reopened the controversy over the creation of hybrids between humans and other animals, even more so because of the use of monkeys, which enjoy greater protection than animals such as mice in the field of scientific experimentation.