All posts tagged: genetics

Massive blood study finds 88,000 new links between genes and metabolism

Massive blood study finds 88,000 new links between genes and metabolism

Published by Jenni Sidey

The chemicals flowing through your bloodstream tell a story that your DNA alone cannot. They reflect what you eat, how your body functions, and even the diseases that may be developing long before symptoms appear. Now, the largest study ever conducted on the genetics of human metabolism has revealed just how deeply our genes shape those chemical signals. Led by researchers at the University of Tartu in Estonia, the study analyzed genetic and metabolic data from 619,372 people. By combining information from the Estonian Biobank and the UK Biobank, scientists created the most detailed map to date of how genetic differences influence hundreds of substances circulating in the blood. The findings uncover tens of thousands of previously unknown links between genes and metabolism. They also challenge some long-held assumptions about disease risk and could help guide future drug development. “This dataset gives us a broad foundation for understanding the pathophysiology of various diseases more deeply and for identifying their causal and drug-targetable factors more precisely,” said Priit Palta, Professor of Translational Genomics at the University …

Are we getting to the point where it’s safe to gene-edit babies?

Are we getting to the point where it’s safe to gene-edit babies?

Published by skeptic

Light micrograph of a human egg cell after fertilisation CC STUDIO/SCIENCE PHOTO LIBRARY When a rogue researcher in China revealed in 2018 that he had used CRISPR to create three gene-edited children, his actions were almost universally condemned by biologists around the world. The main objection was not that gene-editing babies is wrong in itself, but that the CRISPR technique used was not safe and had a very high risk of causing harmful mutations. Now, a team in the US has used an improved form of CRISPR, known as base editing, to edit healthy embryos and shown that it can be done without introducing unwanted mutations. So are we now at the point where we could consider allowing the use of the technique? The answer is no, because a major obstacle remains. Our DNA consists of two strands. The first form of CRISPR to be developed uses a protein called Cas9, which hooks up with a piece of guide RNA that helps it find a specific place in the genome. Once there, Cas9 cuts through both …

A single gene may explain why some males live fast and die young

A single gene may explain why some males live fast and die young

Published by Jenni Sidey

A small fish that lives fast and dies young has given biologists a rare look at one of evolution’s oldest bargains. In the African turquoise killifish, researchers traced that bargain to a single gene called vgll3, which helped push males toward faster growth and earlier sexual maturity. But the same shift also came with a darker side: shorter lives, more age-related tumors, and a higher risk of melanoma-like cancers in old age. The finding offers unusually direct evidence for antagonistic pleiotropy, a long-debated theory of aging that holds that some genes are favored because they improve early-life success, even if they cause damage later on. “We have effectively caught evolution in the act of making a trade-off,” said Dr. Itamar Harel of Hebrew University. “For years, we’ve asked why our bodies can’t just maintain themselves indefinitely. This gene gives us a direct answer: nature doesn’t prioritize longevity; it prioritizes continuity. We are built to sprint, not to marathon.” The killifish is an emerging model for investigating the genetic architecture of aging and age-related pathologies, which …

Huge study of Alzheimer’s genetics identifies new drug targets

Huge study of Alzheimer’s genetics identifies new drug targets

Published by skeptic

Illustration of amyloid plaques, which build up around brain cells in Alzheimer’s disease JUAN GAERTNER/SCIENCE PHOTO LIBRARY/Alamy The biggest genetic study of Alzheimer’s disease so far has identified 127 gene locations that are associated with the condition, of which 48 are new. The study also pinpoints several genes that could be prioritised as drug targets and cell types linked to a higher genetic risk of the condition. “It’s an exciting time for Alzheimer’s genetics,” says Rudolph Tanzi at Massachusetts General Hospital, who provided evidence of the first Alzheimer’s-linked gene, APP, in 1987. Alzheimer’s disease, the most common cause of dementia, is highly heritable, with twin studies showing genetics can account for about 60 to 80 per cent of a person’s risk. Many genes have been found to play a role, chief among which is APOE. Inheriting one copy of a variant of this, known as APOE4, from a parent makes someone two or three times as likely to develop Alzheimer’s as someone without the variant, and getting a copy of APOE4 from both parents can increase risk …

Scientists find hundreds of inherited DNA patterns that defy classic Mendelian genetics

Scientists find hundreds of inherited DNA patterns that defy classic Mendelian genetics

Published by Jenni Sidey

For more than a century, heredity has been framed through the tidy logic of Mendel’s pea plants: traits pass from parent to offspring by fixed genetic rules. But a new mouse study suggests that chemical marks layered on DNA can sometimes slip past those rules, carrying inherited effects in ways standard genetics does not fully explain. That does not mean the basic laws of genetics are suddenly obsolete. It does mean they may not tell the whole story. In this case, researchers found that DNA methylation, a chemical tag that can turn genes on or off without changing the DNA sequence itself, sometimes passed across generations in ways that did not follow the classic patterns of dominance, recessiveness, or simple parental contribution. Looking across three generations of mice, the team identified 522 cases on non-sex chromosomes where inherited methylation patterns broke Mendel’s rules. Those cases made up about 7% of the epigenetic inheritance patterns they tracked, a share large enough to suggest these exceptions are not just biological curiosities. “Non-Mendelian patterns of inheriting epigenetics could …

The Secrets of Our DNA review: New Scientist recommends Turi King’s expert book

The Secrets of Our DNA review: New Scientist recommends Turi King’s expert book

Published by skeptic

DNA evidence both convicted and eventually freed Amanda Knox Oli Scarff/Getty Images The Secrets of Our DNATuri KingUK, Doubleday; US, Transworld Digital In 1993, a 62-year-old woman in the town of Idar-Oberstein in Germany was found strangled with florist wire. DNA found on a coffee cup suggested that two people were present besides the victim and that one of the apparent killers was a woman. In 2001, the suspected female murderer’s DNA turned up again in Germany, this time on the body of a strangled 61-year-old man in Freiburg. Then her DNA started appearing at crime scenes in France and Austria, too. In 2007, the mysterious woman hit the headlines when two police officers were shot – one fatally – in their car in the German city of Heilbronn, and her DNA was found in the back seat. These killings sparked a major hunt for “the Phantom of Heilbronn”, as she became known. But the Phantom proved elusive, despite being linked to 41 crimes via her DNA. In some cases, her accomplices were caught, but …

The Selfish Gene at 50: Why Dawkins’s evolution classic still holds up

The Selfish Gene at 50: Why Dawkins’s evolution classic still holds up

Published by skeptic

Ryan Wills for New Scientist; Alamy; SPL When The Selfish Gene was published in 1976, The New York Times said it was “the kind of science writing that makes the reader feel like a genius”. Few popular science books have had such an impact. As Richard Dawkins writes in the epilogue to the 50th anniversary edition, it’s rare enough for a book to be in press 50 years later, let alone that the author is still around to write an update about it. There is a strong case that The Selfish Gene has had the biggest influence on our understanding of evolution of any book since Charles Darwin’s On the Origin of Species. It showed, in irresistible prose, how everything we see in biology can be explained by a gene-centred view of life. Yet when it was first published, only a small number of genes had been sequenced and we didn’t even know how many we had or shared with other species. So, half a century on, with the “selfish gene” metaphor still very current, …

Intoxicating and astonishing: Why ‘The Selfish Gene’ almost never was

Intoxicating and astonishing: Why ‘The Selfish Gene’ almost never was

Published by skeptic

The Selfish Gene, Richard Dawkins’s first book, was published in October 1976 and 50 years on, it is still selling, in more than 30 languages. For a science book – not least one with “gene” in its title – this is truly astonishing. For me, the story began in February 1976. I was a commissioning editor at the Oxford University Press (OUP) and in the post was a handwritten note from Roger Elliott, a physicist and one of the university academics involved with OUP. He wrote: “One of the dons here, Dr C R Dawkins, is writing a popular science book tentatively called ‘The Selfish Gene’… I have no idea whether he or it is any good but it might be worth looking into.” Just under two weeks later, I started to read draft versions of Dawkins’s opening chapters and, with a jolt, my life changed. I knew before reaching the bottom of the first page that here was something extraordinary. It was as if the writing had reached out and grabbed me by the …

1.3 million people share DNA with Maryland’s earliest colonists

1.3 million people share DNA with Maryland’s earliest colonists

Published by Jenni Sidey

Get the Popular Science daily newsletter💡 Breakthroughs, discoveries, and DIY tips sent six days a week. In 1634, English settlers established St. Mary’s City as the first permanent outpost in the colony of Maryland. Many of these early residents were ultimately buried in the town’s Chapel Field cemetery, including 49 colonists between the town’s founding and 1734. Recently, geneticists collaborating between Harvard University, the Smithsonian Institute, and genetics company 23AndMe analyzed these previously unidentified remains as part of a larger genealogical project tracing colonial migration across the United States. Their findings illustrate how  such a small original population can have vast genetic influences over time. According to the team’s study published in the journal Current Biology, over 1.3 million living descendents can be traced directly to the handful of settlers buried at St. Mary’s City. What’s more, researchers believe that they potentially identified remains belonging to Maryland’s second governor. The results come after decades of work that began with the excavation of a trio of extremely rare lead coffins from the cemetery’s Brick Chapel in …

Study shows how a potato-based diet changed the genetics of Andean people

Study shows how a potato-based diet changed the genetics of Andean people

Published by Sam Flores

May 7 : Indigenous people in the Andes domesticated the potato – a great source of starch, vitamins, minerals and fiber – 6,000 to 10,000 years ago, making this tuber a central part of their diet. These people then experienced genetic adaptations beneficial for such a diet that are still seen in their descendants living in Peru. New genomic research documents how these descendants – speakers of the Quechua language of the once-great Inca Empire – underwent fortification involving a gene called AMY1 that is involved in starch digestion, a function useful for people with a potato-centric diet. The study found that these people possess an average of 10 copies of AMY1 – two to four more than most people. No other known population globally exceeds that number. The study also showed that the onset of these genetic changes in this population coincided with the advent of potato domestication. “It is a wonderful case of culture shaping biology,” said evolutionary and anthropological geneticist Omer Gokcumen of the University at Buffalo, one of the senior authors …