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Study Finds That A Healthy Lifestyle Can Help Combat ‘Life-Shortening’ Genes 

Your genetic makeup plays a major role in shaping your overall health and lifespan. Some individuals are naturally predisposed to living a longer life, while others may have genes that will cause aging to be more difficult for them. 

However, according to a new large-scale study published in the British Medical Journal, healthy lifestyle decisions can help combat those negative predispositions. The study stated that your daily decisions regarding diet, exercise, and other lifestyle choices can cancel out around 60% of the impact of “life-shortening” genes. In fact, a healthy and consistent lifestyle can add another five years to your life, Forbes reported.

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Researchers involved in the study utilized genetic, biological, and health data from 353,742 participants and tracked their health for around 13 years, according to reports. The timespan of the study allowed the researchers to see how lifestyle and genetics specifically interact to influence longevity in life. 

Participants within the study were placed into three lifespan categories based on their genetic makeup, including protective and/or harmful variants. 

20% of participants were in the category of having genes that boost lifespan. Another 20% had genes that set them up for a shorter lifespan, and a majority of the participants, 60%, had genes that were “suggestive of an intermediate lifespan.” 

The researchers also categorized each participant into a lifestyle-score category: favorable (23%), intermediate (56%), and unfavorable (21%), according to Forbes

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These lifestyle “scores” were calculated by analyzing participants’ sleeping habits, diets, their physical activity, and how much they drank or smoked. Healthcare providers and scientists alike tend to agree that the best lifestyle habits attributed to living a long life include never smoking, a healthy diet, getting eight hours of sleep a night, and getting regular exercise. 

Individuals who are genetically predisposed to a shorter life due to their specific genetic makeup are 21% more likely to die at an earlier age compared to those with favorable genes. That percentage remains the same regardless of one’s lifestyle choices. 

One of the points of the study was to show that those with “life-shortening” genes can offset the effects of those genes by more than 60%, allowing them to live a longer and healthier life by nearly 5 years. 

The study also found that those with an unhealthy lifestyle are 78% more likely to die at an earlier age, regardless of their genetic predispositions. Healthy genes cannot protect an individual from the damaging effects of an unhealthy lifestyle. 

A major takeaway that the researchers are hoping the general public will gain from this information is that a healthy lifestyle really can make a difference in how you feel day-to-day.

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Genes That Helped People Survive the Plague Linked to Autoimmune Disorders in Descendants

Scientists have discovered that the same genetic characteristics that helped people survive the Black Death more than 700 years ago are now linked to an elevated risk of developing certain autoimmune disorders.

Using the DNA of victims and survivors of the Black Death from the 14th century, scientists have discovered that Europeans with a variation of the gene called ERAP2 had a substantially better chance of surviving the disease. The mutations provided protection against the Black Death pathogen Yersinia pestis, which went on to kill off nearly half of Europe’s population.

These results, published in the Journal “Nature,” provide insight into how the Black Death influenced the development of immunity genes like ERAP2 and laid the groundwork for how some people react to disease today. For instance, inheritors of the gene have a higher risk for autoimmune diseases such as Crohn’s disease and arthritis.

Luis Barreiro, professor of genetic medicine at the University of Chicago Medical Center and co-author of the study, believes this study provides new insight into the true evolutionary impact of the plague.

“This is, to my knowledge, the first demonstration that indeed, the Black Death was an important selective pressure to the evolution of the human immune system.”

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The study was carried out on more than 500 ancient DNA samples collected from the teeth of people who had died before, during or after the plague. Some samples were taken from skeletons buried in London’s East Smithfield plague pits. According to Barreiro, the pits were used for mass burials in 1348 and 1349 when people were dying so quickly that the city’s cemeteries were running out of space.

“So the king [Edward III], at the time, bought this piece of land and started digging it. There’s basically layers and layers of bodies one on top of each other.”

Samples that contained two copies of the ERAP2 gene indicated an ability to produce functional proteins, which helped the immune system to recognize an infection. The variant also helped immune cells neutralize the virus more efficiently, making the person 40% more likely to survive the plague than their peers. However, the mutations enhanced the body’s inflammatory response, making people more susceptible to autoimmune disorders.

Hendrik Poinar, professor of anthropology at McMaster University in Canada and co-senior author of the study, said the study showed the ability of pandemics to alter genome sequences in the long-term without being detected in modern populations.

“These genes are under balancing selection – what provided tremendous protection during hundreds of years of plague epidemics has turned out to be autoimmune-related now. A hyperactive immune system may have been great in the past, but in the environment today, it might not be as helpful.”

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Evolutionary biologist David Enard from the University of Arizona said the speed of the adaptation over just a few decades had other implications. The 40% survival advantage the variant bestowed is the most significant evolutionary advantage recorded in humans.

“The evolution is faster and stronger than anything we’ve seen before in the human genome. It’s really a big deal. It shows what’s possible [for humans], in terms of adaptation in response to many different pathogens.”

According to paleogeneticist Maria Avila Arcos, the study still has its limitations by only being carried out on a narrow population. The plague also affected parts of Asia and North Africa.

“There might be way more cellular mechanisms people used to cope with this devastating outbreak, but we’re just seeing the mechanisms shared across the English and Danish.”

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Scientists Sequence 5,700-Year-Old Human Genome

Despite rapid scientific advancements over the past several years, little is known about the lives of prehistoric humans, who left behind no written records and few artifacts. However, scientists were recently able to sequence a prehistoric human genome from DNA left in birch pitch, discovered in Denmark, which was used as chewing gum 5,700 years ago and was preserved in mud. This rare insight into our species’ genetic history gives scientists new information about our distant past, particularly with respect to how human beings have changed genetically over the past few millennia due to evolution. The discovery represents a breakthrough in our understanding of prehistoric human life, as the research presents insights into the diet, lifestyle, and genetic makeup of our distant ancestors.

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The results of the research were published by Nature in a paper that provides extensive detail about the methodology used to analyze the birch pitch as well as the implications of this analysis on our understanding of human history. By looking both at the complete human DNA which was found in the pitch as well as DNA from other plants and animals that the prehistoric individual may have eaten, the researchers determined information about the nearly six thousand year old person and extrapolated from this data to speculate about the larger culture she was a part of. 

The human DNA revealed that the person, whom scientists named “Lola,” was female and probably had dark skin, dark brown hair, and blue eyes. Given that the birch pitch was found in Europe, the fact that Lola had dark skin is notable, as it suggests that the spread of the trait of light skin pigmentation did not occur until later in history. Additionally, the DNA showed that Lola was lactose-intolerant, supporting the theory that tolerance to lactose evolved later in the history of human evolution after the beginning of dairy farming.

Lola, and by extension people who lived in Denmark at the time, likely lived a hunter-gatherer lifestyle, suggesting that this lifestyle persisted for longer in prehistory than scientists had previously assumed. In addition to providing a complete picture of Lola’s genome, the tree birch sample also gave scientists a snapshot of her “oral microbiome signature,” or the various species of bacteria that lived in her mouth at the time. 

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One of the species of bacteria they discovered was Streptococcus pneumoniae, suggesting Lola may have been suffering from a respiratory infection at the time. They also found evidence that Lola may have had mononucleosis, commonly known today as “mono.” Additionally, the scientists found DNA from animals and plants that were likely part of Lola’s diet, including hazelnut and mallard, supporting the opinion that Lola and the people living around her primarily found their food by hunting and gathering. While the evidence provides a genetic snapshot of a moment in Lola’s life, other details of her story, including her age and the cause of her death, will likely never be known.

 

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Doctor Claims Genetically Modified Babies Only Two Years Away

An academic from Abertay University in Dundee, Scotland, has claimed we are only two years away from being able to create ‘ethically sound’ designer babies.

Gene editing risks are at an all time low meaning there are high levels of justification to use the technique on human embryos, claims Dr Kevin Smith.

Dr Smith also highlights the fact that genetically modified (GM) people could be morally justifiable within a few years, which in turn could assist in preventing certain diseases from being passed through generations as well as improving the quality of life once the GM baby reached an older age.

The process of gene editing can be very complex with scientists altering an organism’s DNA to help prevent diseases being spread, however using this technique on human DNA will always be a topic that will bring heated debate, with the theory that if the process gets passed into the wrong hands the reasons for conducting the practice could be changed, for instance helping families choose the colour of their baby’s eyes, hair and more.

‘The human germline is by no means perfect, with evolution having furnished us with rather minimal protection from diseases that tend to strike in our later years, including cardiovascular disease, cancer and dementia. GM techniques offer the prospect of protecting future people against these and other common disorders. This has previously been achieved to an extent in GM experiments on animals. If several common disorders could be avoided or delayed by genetically modifying humans, the average disease-free lifespan could be substantially extended.’

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Yet however ethically sound the process may have been described as, there are worries that a revolution in genetic modification could begin and Dr Smith has warned there must be an ethical approach if there is any chance of winning the trust of the public.

‘Society is largely opposed to genetically modifying humans and the negative publicity generated by the ethically problematic first-ever production of GM babies in China last year was strongly criticized by most geneticists and ethicists, further hardening attitudes against the creation of so-called ”designer babies”.’

‘However, by delaying an ethically sound move towards a world where we can reduce genetic disease, we are failing those who suffer through disease and debilitating conditions. If such negative attitudes to biomedical innovation had prevailed in the 1970s, the development and use of IVF – a massively beneficial medical technology – would have been severely delayed, and indeed might never have come to fruition.’

A highly controversial topic of debate, gene-edited babies were born in China amongst fierce claims of law breaking. Twins Lulu and Nana were born in November 2018 thanks to Chinese Scientist Prof He Jiankui who was condemned by several researchers, bioethicists and medical professionals who claimed he acted illegally ‘in pursuit of fame and fortune’.

However this was not the first time scientists had edited the DNA in human embryos. In 2017, scientists in the United Kingdom were experimenting with human embryos that had been donated by IVF couples who no longer required them.

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There are many claims to why genetically modified babies should be looked at with caution. Not only are there concerns about the potential side effects there are also ethical fears being raised, such as the chance for inequality becoming a bigger issue thanks to the wealthiest of people being able to produce genetically enhanced children, therefore increasing an already large gap between the poorest and richest people in the world. There are also concerns that long-term, potentially specific aspects to the human race could be eradicated completely.

Dr Smith has also stated that the latest studies have shown that the main way forward in the war against multiple disease-associated genes is to use genetic modification within an embryo. The human germline, which is cells that span across multiple generations, is ‘by no means perfect’ thanks to evolution giving precariously low levels of protection from diseases that are more prevalent in our older years.

‘GM techniques offer the prospect of protecting future people against these and other common disorders. This has previously been achieved to an extent in GM experiments on animals’
There have been many questions surrounding the ethical side of creating genetically modified babies with Dr Smith commenting they were ‘highly desirable’.

The theory that common disorders and diseases could be delayed, or even avoided altogether, resulting in the average human lifespan being ‘substantially extended’.

The doctor also questioned whether the delay in creating a world without genetic disease through genetic modification was failing those who currently suffer conditions that are not only debilitating but also life threatening.

If genetic modification on human embryos does become more common it is agreed that there will have to be safeguarding measures put in place, not just to protect the families involved, but also to protect the way that the technique is used in years to come.