What makes us altruistic – and what's it good for?

• Book information


• Does Altruism Exist? Culture, Genes, and the Welfare of Others by David Sloan Wilson


• Published by: Yale University Press


• Price: $27.50/£16.99

• Book information


• The Altruistic Brain: How we are naturally good by Donald W. Pfaff


• Published by: Oxford University Press USA


• Price: $24.95/£16.99

Does giving money to people who beg constitute true altruism? (Image: Giacomo Pirozzi/Panos)

Two new books use the latest brain science to figure out what makes us behave selflessly – and also suggest practical steps for encouraging it

IN 1851, Auguste Comte, the French philosopher and father of sociology, coined the word altruisme (from the Latin for "others") as part of a drive to create a non-religious religion, based on scientific principles.

He defined it as "intentional action, ultimately for the welfare of others that entails at least the possibility of either no benefit or a loss to the actor", recognising it as one of the two most important findings of modern science, with the discovery of the motion of Earth. At that time, studies of animal behaviour and phrenology led him to locate egotistical instincts at the back of the brain, altruistic ones at the front.

Today, we have a far more sophisticated knowledge of the neurological and biochemical factors that underpin benevolent behaviour. And this science forms the bedrock of two books aimed at general readers – but also at those who, despite the research, still doubt the existence of altruism.

However, the books may end up inadvertently providing more ammunition for the naysayers. Take The Altruistic Brain by neuroscientist Donald Pfaff. On solid scientific ground, he builds a five-step theory of how altruism occurs, which hinges on an idea that is both unconvincing and counterproductive. Pfaff argues that to act altruistically you should first visualise the recipient of your goodwill, then mentally transform their image into your own, "from angle to angle and curve to curve". How narcissistic!

At the core of evolutionary biologist David Sloan Wilson's Does Altruism Exist? is another contentious idea: altruism has evolved as the result of group selection. But Wilson argues his corner masterfully, providing a pithy riposte to the belief that natural selection occurs only at the level of the selfish gene: "Selfishness beats altruism within groups. Altruistic groups beat selfish groups," he says.

In other words, we cooperate when doing so gives our team the edge. That doesn't sound very selfless either.

Wilson acknowledges this, but argues that thoughts and feelings are less important than actions. According to evolutionary theory, pure altruists do exist, but it doesn't matter why people choose to help others – their reasons may be opaque even to themselves. What matters is that humans can coordinate their activities in just the right way to achieve common goals. Other animals do this too, but we are masters. "Teamwork is the signature adaptation of our species," he says.

Pfaff goes further, insisting that our brain biology "compels us to be kind". He believes this knowledge alone will inspire individuals to be more altruistic. His desire to create a better world is admirable and some of his ideas are interesting, but Wilson's analysis is more coherent and nuanced.

While it is in our nature to be altruistic, Wilson says, we also have a healthy regard for self-interest and a resistance to being pushed around. Which predisposition comes to the fore depends on the environment in which we find ourselves. Ethics, he says, cannot be taught at individual level, but are "a property of the whole system".

Wilson's fascinating gallop through religion, economics, politics and everyday life reveals many ways to activate altruism. Take his Neighborhood Project, where he designs environments to select for prosocial behaviour. By doing this, he and others promote measures to help groups function better, by, say, encouraging equality or discouraging free-riding. Not pure altruism, sure, but sound science. Comte would be impressed.

This article appeared in print under the headline "The greater good"

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Today on New Scientist

Dead star leaves behind Jupiter's Ghost

Not every star ends with a bang. A beautiful post-mortem portrait reveals a cloud of gas surrounding a jewel-like white dwarf

Lava could have preserved the origins of life on the moon

New experiments suggest that if life-bearing meteorites hit the young, molten moon, they could have been preserved until today

Wave function gets real in quantum experiment

Is the uncertainty that comes with the quantum wave function real or a mathematical quirk? An experiment has found in favour of fuzziness

Ancient microbes formed Earth's biggest hoard of gold

Early life forms may have extracted gold from water and dumped it in South Africa's El Dorado, the source of half the gold ever mined

New treatment for endometriosis preserves fertility

Two promising new drugs could treat pain and infertility in a common reproductive disease while still allowing women to conceive

Urban rabbits downsize to smaller, 'studio' warrens

The European rabbit is under pressure in the countryside but is successfully embracing city life – with a twist

Virtual hearts get to the crux of sudden cardiac death

Watching hundreds of genetically different hearts beating in a supercomputer is helping doctors identify who is at risk from unexpectedly dropping down dead

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Ozone hole: How we are misled in the fight to cut smog

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Obama wants to cut ozone pollution, but Republicans are crying foul over the cost. Europe is being tougher… or is it? Much is obfuscation

"VOTE Republican: vote smogs". I doubt many bumper stickers carried that message during last year's US midterm elections. But choking air and kids dying of asthma may be what the Republican victory delivers.

Republicans now control both houses of Congress and are all for throttling President Barack Obama's plans to lower the federal limit on ozone smog, announced by the US Environmental Protection Agency (EPA) right after the elections. They say it is unachievable, except at vast cost.

This might surprise Europeans, who have been living with a tougher limit for some time. However, an analysis for New Scientist suggests that Europe's limits are less stringent than they appear. And reports from Brussels in recent weeks suggest that anything tougher is off the agenda because of concern about the impact on fragile economies.

Ozone in the stratosphere, miles above the ground, is a good thing, shielding us from cancer-causing ultraviolet radiation. But it is also a strong corrosive oxidant. At street level it triggers asthma attacks, damages children's lung development and causes heart problems in the elderly. It also cuts crop yields, slows tree growth and eats away at textiles – all at levels commonly found in industrialised nations.

The pollutant is unusual in that we don't emit much directly. It is largely a secondary product, created photochemically. Nitrogen oxides from burning fuel react in sunlight with volatile organic compounds from solvents plus vehicle engines and oil refineries. This cocktail brews especially in summer, though it takes a few hours for the concentration of ozone to peak, so the highest levels are often found in suburbs or countryside downwind of urban areas, where pockets of pollution will have drifted in those few hours.

The health risks scale up with the duration of continuous exposure; regulators mostly measure 8-hour averages. Places breach limits when they have too many days with excessive amounts over 8-hour stretches.

The first US ozone standard was set in 1979, at 120 parts per billion. It was lowered in 1997 to 84 ppb and again in 2008, under President Bush, to 75 ppb. Many major US cities such as Chicago, Dallas, Houston and much of California regularly breach the Bush limit.

But doctors say the limit should be lower still. The World Health Organization reports that healthy adults and children exposed to ozone at 60 ppb for several hours experience inflamed lungs and breathlessness. In 2005, the WHO recommended a limit of 50 ppb.

Regulators have been timid. The Obama administration initially vetoed a tougher stance. But last November, the EPA finally proposed a new limit of between 65 and 70 ppb. It would come into force between 2020 and 2037, with problem cities getting most time to adjust. "Bringing ozone pollution standards in line with the latest science will clean up our air [and] protect those most at risk," said EPA administrator Gina McCarthy. But 2037 is a long time to wait if you have asthma.

Opponents say meeting such a limit will require expensive retrofitting of scrubbers to remove nitrogen oxides from power plant fumes, and either new technology for vehicle exhausts or limits on transport. It "could cost up to $270 billion a year and place millions of jobs at risk", according to the US National Association of Manufacturers. The EPA dismisses that, reckoning that a 65 ppb limit would cost $15 billion a year in return for health benefits worth twice as much: annually, up to 4300 fewer premature deaths, as many as 960,000 fewer childhood asthma attacks, and a million fewer missed schooldays.

In the dog days of his administration, Obama is keen to use his executive powers to bring on environmental measures of this sort. But Congress is not in a mood to lie down. Both the Senate and House of Representatives are looking at Republican proposals requiring the EPA to consider the impact of air-quality rules on jobs, something it is not allowed to do at present. Republicans may also take aim at EPA funding. Smog sceptics, like climate sceptics, seem to have subjugated environmental concerns to their narrow political agenda.

All this makes Europe look good. A European Union ozone limit of 60 ppb – deemed unattainable in the US – has been in force since 2010. But US and European limits are not directly comparable, and here's why.

In the US, being in breach of the regulations means exceeding the limit on four or more days in a year, averaged over three years. So 11 breaches in any three-year period is fine, but 12 is not. In Europe, the limit can be exceeded up to 25 days a year, again averaged over three years. So up to 75 bad-air days are allowed in that time. That's a lot, but even so large parts of southern Europe failed that test for the period 2011 to 2013, because of a spike during the hot summer of 2013.

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Dead star leaves behind Jupiter's Ghost

(Image: ESA/XMM-Newton & Y.-H. Chu/R. A. Gruendl/M. A. Guerrero/N. Ruiz (X-ray); NASA/ESA Hubble Space Telescope & A. Hajian/B. Balick (optical))

When small and medium-sized stars die, they don't explode. Instead, they peacefully expand, creating clouds while they shed their outer layers like a dandelion.

This image shows an example of one of these celestial remnants, named Jupiter's Ghost because it takes up about the same amount of space in the sky as the planet Jupiter.

The jewel-like white dwarf star in the centre of the cloud is releasing super-strong stellar winds. They plough into the gas surrounding the star, heating it to over two-million degrees centigrade and causing it to emit X-rays, shown in blue. The green glow of the outer layers represents cooler gas that emits light visible to the human eye, while flame-shaped pockets of even cooler gas are shown in red.

The picture combines X-ray observations, collected by ESA's XMM-Newton spacecraft in 2003, with images in the visible range captured by the Hubble Space Telescope.

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Lava could have preserved the origins of life on the moon

Fossils on the moon may be our best bet for discovering the origins of life in our solar system. New experiments suggest that if the precursors to life arrived on Earth encased in a comet or asteroid, the moon could have preserved a record of it, despite being covered in lava at the time.

The simplest forms of life appeared on Earth some 3.8 billion years ago, but scientists still have no idea how. Since that crucial time, Earth's tectonic forces have destroyed almost all the rocks that might have kept records of the beginnings of life. "Both geology and life are efficient recyclers and hinder preservation," says Mark Sephton from Imperial College London.

Some think that rather than originating on Earth, life or its organic precursors could have been delivered on asteroids, comets or fragments from other planets. If so, similar rocks should also have hit the moon – which is in better shape to preserve them. "The moon has been geologically quiet for billions of years," says Richard Matthewman of Imperial College London. Furthermore, previous studies have suggested that organic compounds flung to the moon from Earth could survive the crash landing.

But when life was emerging on Earth, the moon was covered in flows of lava. Sephton, Matthewman and their colleagues wondered: would that lava destroy the organic record on the moon?

Lava life preserver

In a series of experiments, they showed that far from destroying organic chemicals, the lava may have "sandwiched" them and preserved them for billions of years.

The researchers put various organic compounds and signatures of life in fake moon dust and then heated it to as high as 700 °C. Their results suggest that organic molecules would only need to be buried a few tens of centimetres below the surface of the rock they arrived in to survive the heat of the molten moon – even if the rock was covered with a layer of lava one-metre thick. And as long as the compounds endured the high temperatures, the lava would have protected them from solar wind, radiation and meteorite impacts.

That means that anything that hit Earth at the time life appeared here might be preserved on the moon. "Evidence of prebiotic evolution on asteroids and comets or the emergence of life on Earth and Mars could all be preserved," says Sephton. "It is an ironic possibility that one of the best places to look for records of early life is our dry and lifeless Moon."

Mark Burchell of the University of Kent in the UK, who ran the earlier study showing that Earth's organics could survive the trip to the moon, calls the team's work "comprehensive and carefully done". He thinks that the moon is an underappreciated source of answers about the origins of life on Earth.

Journal reference: Astrobiology, DOI: 10.1089/ast.2014.1217

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Ancient microbes formed Earth's biggest hoard of gold

Where there was life, there may be gold. Some of the oldest life forms may have played a crucial role in the formation of what's now the Earth's largest known gold reserve.

The process could only have taken place during a window of opportunity after life on land came to being and before it created the planet's oxygen-rich atmosphere. This means such gold deposits could not be formed today – but it potentially gives us a new way to find them.

Approximately 40,000 metric tonnes of gold have been mined from the Witwatersrand Basin in South Africa since its discovery in 1886. That's three times more than from any other single source and roughly half the gold ever been mined on Earth.

The gold accumulated 3 billion years ago. But how it did so has been a matter of geological debate.

Golden eruption

There's little doubt that the gold first reached the Earth's surface through the erosion of gold-bearing veins in a granite mountain range called the Kaapvaal Craton in what is now north-east South Africa. The precious metal came up with the lava that formed the mountains.

But it is unclear how huge quantities of this gold ended up several hundred kilometres to the south west in the Witswatersrand basin.

The prevailing theory is that metallic gold fragments were eroded from the Craton mountains and transported by rivers that dumped their cargo in shallow lakes overlying what is now the gold-rich basin.

"The idea is that it arrived by mechanical transportation together with sediments, like gold washing into creeks and gullies," says Christoph Heinrich of the Swiss Federal Institute of Technology in Zurich, Switzerland. He disagrees.

Heinrich argues that the gold was first dissolved chemically by volcanic rain and then washed to the basins by river. It was then precipitated out of the water by mats of microbes growing in shallow pools of the Basin.

"We don't know if the gold precipitated out during life or after they died, but basic chemistry tells us that organic life reduces gold chemically from the ionic to the elemental form," Heinrich says.

No oxygen

Central to his theory is that 3 billion years ago, the atmosphere was still largely free of the oxygen that was produced half a billion years later by algae and cyanobacteria during the Great Oxidation Event.

Before this event, the air was full of gases containing sulphur – such as hydrogen sulphide – that were pumped out by volcanoes and rained down on the mountains in acid rain. The gold would have formed soluble complexes with sulphur, which were then absorbed in water and finally separated by the primitive microbes, leaving behind today's rich legacy of elemental gold.

This was only possible because there was so little oxygen in the atmosphere at the time, says Heinrich. If oxygen had been there, it would have reacted with and destroyed the sulphide-based gold complexes before they could reach the shallow, life-bearing pools. "Oxygen would have 'killed' the sulphur compounds that carried the gold," he says.

"The billion-dollar question is whether the same process created other gold deposits," says Heinrich.

If it did, then it may provide new geological clues for today's gold prospectors. Currently, he says that searches tend to focus on gravel-rich areas like those that gave rise to the Californian gold rush. But if gold was transported in solution rather than as grains, and later extracted by early life forms, this may open up new ways to trace untapped deposits, he says.

So where would he look for gold? "I would look for carbon because if I'm right, carbon is an essential part of it," says Heinrich. "So I would maybe look for carbon-rich shale in the same lake-type environments but without the gravel."

Heinrich's theory is worth serious consideration and further testing, says Jan Kramers of the University of Johannesburg in South Africa. "It works well with the now well-established observation that the atmosphere was not oxidising and the rain was more acidic than today, and it's hard to fault the arguments for transport of gold in solution under these conditions, followed by precipitation in the presence of organic matter."

Journal reference: Nature Geoscience, DOI: 10.1038/NGO2344

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Wave function gets real in quantum experiment

It underpins the whole theory of quantum mechanics, but does it exist? For nearly a century physicists have argued about whether the wave function is a real part of the world or just a mathematical tool. Now, the first experiment in years to draw a line in the quantum sand suggests we should take it seriously.

The wave function helps predict the results of quantum experiments with incredible accuracy. But it describes a world where particles have fuzzy properties – for example, existing in two places at the same time. Erwin Schrödinger argued in 1935 that treating the wave function as a real thing leads to the perplexing situation where a cat in a box can be both dead and alive, until someone opens the box and observes it.

Those who want an objective description of the world – one that doesn't depend on how you're looking at it – have two options. They can accept that the wave function is real and that the cat is both dead and alive. Or they can argue that the wave function is just a mathematical tool, which represents our lack of knowledge about the status of the poor cat, sometimes called the "epistemic interpretation". This was the interpretation favoured by Albert Einstein, who allegedly asked, "Do you really believe the moon exists only when you look at it?"

The trouble is, very few experiments have been performed that can rule versions of quantum mechanics in or out. Previous work that claimed to propose a way to test whether the wave function is real made a splash in the physics community, but turned out to be based on improper assumptions, and no one ever ran the experiment.

What a state

Now, Eric Cavalcanti at the University of Sydney in Australia and his colleagues have made a measurement of the reality of the quantum wave function. Their results rule out a large class of interpretations of quantum mechanics and suggest that if there is any objective description of the world, the famous wave function is part of it: Schrödinger's cat actually is both dead and alive.

"In my opinion, this is the first experiment to place significant bounds on the viability of an epistemic interpretation of the quantum state," says Matthew Leifer at the Perimeter Institute in Waterloo, Canada.

The experiment relies on the quantum properties of something that could be in one of two states, as long as the states are not complete opposites of each other: like a photon that is polarised vertically or on a diagonal, but not horizontally. If the wave function is real, then a single experiment should not be able to determine its polarisation – it can have both until you take more measurements.

Alternatively, if the wave function is not real, then there is no fuzziness and the photon is in a single polarisation state all along. The researchers published a mathematical proof last year showing that, in this case, each measurement you make reveals some information about the polarisation.

Get real

In a complicated setup that involved pairs of photons and hundreds of very accurate measurements, the team showed that the wave function must be real: not enough information could be gained about the polarisation of the photons to imply they were in particular states before measurement.

There are a few ways to save the epistemic view, the team says, but they invite other exotic interpretations. Killing the wave function could mean leaving open the door to many interacting worlds and retrocausality – the idea that things that happen in the future can influence the past.

The results leave some wiggle room, though, because they didn't completely rule out the possibility of some underlying non-fuzzy reality. There may still be a way to distinguish quantum states from each other that their experiment didn't capture. But Howard Wiseman from Griffith University in Brisbane, Australia, says that shouldn't weaken the results. "It's saying there's definitely some reality to the wave function," he says. "You have to admit that to some extent there's some reality to the wave function, so if you've gone that far, why don't you just go the whole way?"

Journal reference: Nature Physics, DOI: 10.1038/nphys3233

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New treatment for endometriosis preserves fertility

Two new drugs are the first to treat endometriosis without harming fertility. Researchers hope they will one day help the 10 per cent of women of reproductive age who suffer from the condition, which can cause infertility and chronic pain, and costs the US $20 billion dollars each year.

Endometriosis is a relatively common condition in which cells that normally grow only in the uterus travel into the abdominal cavity, where they form lesions and cysts, scarring organs such as the ovaries, fallopian tubes, bladder and rectum. These lesions also lead to inflammation and nerve growth, causing abdominal pain.

The condition causes infertility in up to 50 per cent of women who have it. Surgically removing lesions or cysts can temporarily relieve pain until they grow back, but a longer-term solution is to reduce levels of the hormone oestrogen throughout the body. Like healthy endometrial tissue in the uterus, the lesions and cysts rely heavily on oestrogen to grow and survive, but reducing the hormone throughout the body has unfortunate side effects, such as menopausal symptoms and infertility. Women with endometriosis who want to have children may face a catch 22 situation – they need to treat their condition to conceive, but this hormonal treatment makes them infertile. Stop the treatment and fertility may return, but so too do the lesions.

But there might be a solution. Through several experiments, Benita Katzenellenbogen of the University of Illinois at Urbana-Champaign and her colleagues discovered that the oestrogen receptors in lesions are different from those found in normal reproductive tissue. Because of this, she and her team have been able to develop two drugs that only affect those receptors in the wayward endometrial tissue.

Avoiding surgery

When given to mice, the drugs – called chloroindazole and oxabicycloheptene sulfonate – reduced the size of existing endometrial lesions and stopped the growth of new lesions. The team thinks that the drugs work in part by interfering with inflammation pathways.

The compounds prevented the development of new nerves in the lesions and also decreased pain. Crucially, neither of the drugs altered the rodents' fertility or the health of their pups.

The drugs also had a similar effect on human endometrial tissue taken from cysts that had been removed from patients. "We are hopeful that these compounds will prove to be useful for women with this common disease," says Katzenellenbogen, although she adds that it may be several years before human trials can start.

Christian Becker, a consultant gynaecologist and endometriosis specialist at the University of Oxford, says the research is encouraging. "It's fascinating to see the drugs had very little effect on the [normal] endometrial tissue and the pups, but we have to wait to see whether this will hold up in humans."

He says it would be good to avoid surgery if possible – he has seen people who have had to endure ten rounds of keyhole surgery to treat the condition. "It's good that this is getting some attention as it affects so many people, but it's not historically been a cool thing to talk about," he says.

Journal reference: Science Translational Medicine, DOI: 10.1126/scitranslmed.3010626

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Urban rabbits downsize to smaller, 'studio' warrens

European rabbits are in decline in rural areas, yet holding strong in cities. But urban living also comes with a changed lifestyle: instead of being packed into complex burrows, city rabbits seem to live a more solitary life in smaller burrows.

Madlen Ziege from the University of Frankfurt, Germany, and her colleagues studied the burrow structures of several populations of European rabbits from urban, suburban and rural sites in and around Frankfurt.

They found that the closer to the city the burrows were, the smaller, simpler and less populated they became. "I did not expect to find such a clear correlation," says Ziege.

So why are urban rabbits downsizing? For one thing, rabbits usually form larger groups when food and burrowing sites are in short supply. Surprisingly, this is not the case in cities, where rabbits may colonise parks, for example.

"Cities are providing a constant and high food supply through human waste and deliberate feeding, as well as access to vegetation cover, such as shrubs," says Ziege. "Many areas in modern cities are often structurally highly diverse and the urban rabbit population could be benefiting from this."

In contrast, she says, rural areas in Germany are now typically characterised by open landscapes with scarce vegetation cover.

Predator pressure

Living in large groups also helps rabbits conserve heat in winter, but there is less need to do that in cities where the microclimate tends to be warmer. Then there is the threat from predators.

"In rural areas, rabbits might be exposed to higher predator pressures and are therefore forced to live in large burrows," says Néstor Fernández of the Doñana Biological Station in Seville, Spain. Complex burrows with many exits help rabbits survive attack, but are clearly a major undertaking. "Building burrows requires investing a lot of energy, and individual rabbits can increase their fitness living and contributing to expand existing burrows, particularly under high predator pressure."

It's unclear whether similar patterns in burrow types will be found across Europe, but Ziege says more research could give us key insights into successfully managing rabbit populations and avoiding damage they may cause to vegetation and even buildings.

European rabbits are listed as near threatened by the IUCN, with populations in decline especially in Spain and Portugal, which they are native to.

Cities have the potential to serve as new habitats for wildlife and in the case of Germany they might even play an important role by acting as a "source" from which rabbits can recolonise rural areas, Ziege says.

Journal reference: Journal of Zoology, DOI: 10.1111/jzo.12207

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Virtual hearts get to the crux of sudden cardiac death

Virtual human hearts beating on supercomputers are helping get to the bottom of the most mysterious of heart diseases – sudden arrhythmic death syndrome.

When someone dies suddenly and unexpectedly, there is often an underlying cardiac problem. If a post-mortem doesn't find one, sudden arrhythmic death syndrome (SADS) is recorded as the cause. SADS can result from a number of genetic conditions that affect the way electrical signals pass through the cardiac muscle making the heart beat. One day – often during physical exertion – the person's heart may begin to beat in a fast, uncontrolled way. This can kill them if their heart doesn't right itself quickly enough. Around 1.3 deaths in every 100,000 can probably be attributed to SADS, and the same genetic problems may also play a role in sudden infant deaths.

If someone has the genetic mutations, they can be treated with drugs or have a defibrillator implanted in their chest. But how do you work out who is at risk? Genetic tests can help but not everyone with the altered genes seems to have the syndrome. Electrocardiograms or ECGs can measure the heart's electrical activity, but exactly how features on the ECG relate to risk is not fully understood.

All in the t-wave

Enter the virtual heart. By running hundreds of genetically customised hearts on a supercomputer, each for many thousands of beats, Adam Hill and his colleagues from the Victor Change Cardiac Research Institute in Sydney, Australia, have cracked some of the secrets of SADS.

One sign that someone has the genetic condition that most commonly leads to SADS, known as long QT syndrome, is a distinctive bump or notched t-wave in their ECG readout. "For the past 30 years, that notched t-wave has been in the diagnostic criteria but nobody's known what's caused it," says Hill. "We show what causes it."

With the wealth of virtual data created by running the simulations, they were able to establish that the more extreme the bump in the ECG is, the higher a person's risk of dying. What's more, they found the main genes thought to cause the problem can be either amplified or compensated for by complex combinations of other genes.

Better diagnosis

"We show that the degree of t-wave notching is correlated with how much risk they are at," says team member Arash Sadrieh. "So person A can have the mutation [but his ECG shows] he's absolutely normal, so you don't need to do the complex surgery to prevent sudden cardiac death. And if his sister has a more notched t-wave, then she is at more risk."

It would have been impractical to use real hearts for this research as you'd need huge numbers of people with specific genetic combinations, all with their full genome sequenced, hooked up to an ECG for days.

Hill says the team has taken the virtual trial data, applied it to patient records of ECGs and found the finer grained analysis of the ECG led to more accurate diagnoses. They're also making progress using the simulations to distinguish between different types of long QT syndrome.

"The work is quite a milestone in terms of how thoroughly they've investigated this issue of the notched t-wave…and how you interpret it," says Peter Hunter from the University of Auckland in New Zealand, one of the world's leading cardiac modelling experts. "This has pushed it to a new level."

Journal Reference: Nature Communications, DOI: 10.1038/ncomms6069

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