After Extensive Data Gathering and Analysis—Plus a Worldwide Media Frenzy—NASA’s Famed Twins Study has Begun to Yield Results


It has been called the most comprehensive analysis of individual human beings ever conducted in scientific history. In March 2015, astronaut Scott Kelly rode a Soyuz spacecraft to the International Space Station and proceeded to spend 340 days in orbit as part of an in-depth study of the long-term effects of space travel on the human body. As rare and valuable as that effort was—representing the longest-ever space mission for a NASA astronaut—it was all the more remarkable thanks to a tantalizing offer from Kelly’s identical twin brother: Mark Kelly, himself a retired astronaut. Since Mark was staying on terra firma, he volunteered to serve as an experimental control, allowing scientists to compare two genetically identical men—one on Earth, the other in zero gravity some 220 miles above it, traveling at almost five miles per second.


The cover of Science featuring the Twins Study.

During Scott’s time on the space station (as well as six months before and after his mission), the brothers underwent physical and cognitive testing and contributed numerous blood, urine, saliva and fecal samples for analysis. Dubbed the NASA Twins Study, the effort comprised 10 interconnected research projects—on such topics as cognition, cardiovascular health, genomic changes, immune response, and the composition of gut, skin and oral bacteria—funded by a total of $1.5 million in agency grants and involving dozens of investigators around the country and abroad.

One of those projects, which focused on how Scott’s environment affected how his genes were expressed and regulated, was led by Weill Cornell Medicine’s Dr. Chris Mason—and along with the nine others, it would make headlines around the world. In April, the Twins Study landed on the cover of the journal Science, which featured a 20-page article summing up the results—the first publication of what’s expected to be many, as researchers continue to parse a mother lode of data. “Overall, the Twins Study is a tour de force about how the body’s adaptability extends to outer space,” says Dr. Mason, the WorldQuant Foundation Research Scholar in physiology and biophysics and an associate professor of neuroscience, of physiology and biophysics, and of computational genomics in computational biomedicine. “The vast majority of changes we saw returned to normal—but about 8 or 9% remained. So it also shows that the body was still to some degree adapting to terrestrial life, even six months after Scott Kelly returned to Earth.”

Among the Mason Lab’s findings were that thousands of genes became active in Scott while remaining dormant in Mark—an effect that became more marked the longer Scott stayed in space. Those genes included ones that play a role in repairing damaged DNA—which may reflect the fact that while in space, Scott was exposed to nearly 50 times as much radiation as his brother was on Earth. Also active were genes related to inflammation, which could be due to the inherent stresses of space travel on the human body; these include the effects of being in zero gravity, such as fluid shifts and bone loss. For Dr. Francine Garrett-Bakelman, who was the first author on the Science paper, the findings made sense. “I’m a physician-scientist, and as a physician, I thought, ‘Yes, an astronaut is under significant stress,’” says Dr. Garrett-Bakelman, who completed her research and medical postgraduate training at Weill Cornell Medicine (where she was an instructor and an assistant attending physician at NewYork-Presbyterian/Weill Cornell Medical Center while working in Dr. Mason’s lab and that of Dr. Ari Melnick, the Gebroe Family Professor of Hematology/Oncology).  She is now an assistant professor of medicine and of biochemistry and molecular genetics at the University of Virginia School of Medicine, as well as an adjunct assistant professor of medicine at Weill Cornell Medicine. “He gets launched into space, spends a year in a foreign environment, then comes down to Earth subjected to a tremendous amount of g-forces. It tells us that the human body is resilient and responding normally to a stressful situation.”


MIRROR IMAGES: Twins Mark (left) and Scott Kelly. Opposite page: Scott on a spacewalk—his third—in December 2015. Credit: Robert Markowitz/ NASA / Johnson Space Center

As Dr. Mason notes, a particularly striking finding was the extent to which Scott’s immune system was on high alert once he went to space: every type of immune cell the researchers measured was active at levels that are practically unheard of. And in fact, Dr. Mason says, the response was even more dramatic when Scott came home. “In his memoir, he says that when he landed back on Earth he didn’t feel well—and we could see why very clearly, in his blood work and gene expression data,” says Dr. Mason, who is also a cofounder, equity stakeholder and consultant for Onegevity Health, a company that provides a comprehensive molecular portrait and customized recommendations for an individual’s health based on integrated analysis of longitudinal blood, genetics and microbiome profiles. “There were all these markers for inflammation and for immune cells kicking into high gear. His body was basically having this moment of, ‘Wow, I’m back in gravity’—these markers in the bloodstream were sometimes 4,000% higher than normal. So we could see that while going to space was hard on the body, returning to gravity was, in some ways, even harder.”

One of the Twins Study’s most surprising discoveries related to telomeres, sections of DNA located at the ends of chromosomes. Normally, as people get older their telomeres get shorter—and researchers had expected to see that happen in space, possibly even faster due to stress and radiation exposure. But in fact—as an investigator at Colorado State University discovered and the Dr. Mason Lab confirmed with new DNA sequencing and analysis methods—Scott’s telomeres got longer, though they reverted to normal after he came home. Why? Researchers don’t yet know. “We need to do a lot more science on this,” says Dr. Cem Meydan, a research associate in the Dr. Mason Lab and a co-first author on the Science paper. “We need to find out why this is happening, and whether we can prevent it or study it for other health-related purposes, such as to fight cancer or aging.”

Dr. Mason and his colleagues emphasize that when it comes to understanding how the human body reacts to being in space, the Twins Study had an obvious and inherent limitation: it had only one subject who actually went aloft. Furthermore, says Dr. Garrett-Bakelman, “this was a single study of one white male; what happens in women, or in people from other racial or cultural backgrounds, we have no idea. Trying to infer anything at all is very difficult without having additional subjects’ data to look at.” And of course, given that the Kelly brothers were NASA’s first (and so far, only) identical twin astronauts, in many ways the study was a one-of-a-kind opportunity. “As a geneticist, I wish every person was a twin or a triplet so we could study them,” Dr. Mason says with a laugh. “It’s unclear if or when this will happen again. It’s going to be hard to match this study anytime soon.” Still, when it comes to figuring out whether humans could survive a mission to Mars or beyond, he and his colleagues call the study’s findings highly encouraging. “Obviously it’s a sample size of one, so it’s hard to make generalized statements—but if we saw similar results in multiple people, I think it bodes well for long-term space travel,” Dr. Meydan says. “Most of the changes we saw can potentially be targeted; in the next five or 10 years, we could develop drugs, interventions or other technology such as shielding for radiation or clothing for reversing fluid shifts in the body.”

Dr. Mason also points out that the Twins Study could have benefits beyond the findings themselves; some of the procedures and analytic techniques its researchers developed could be a boon to terrestrial medicine. “It forced us to be nimble with limited numbers of cells and to sequence really quickly,” he says, noting that their methods could inform rapid diagnosis of infectious pathogens or genetic analysis of a cancer patient’s tumor. Working with some of the same collaborators as in the Twins Study, Dr. Mason’s team also helped pioneer the first-ever DNA sequencing experiments on the International Space Station. Plus, Dr. Garrett-Bakelman says, the study stands as a prime example of how broad scientific questions can be answered through large-scale collaboration. “If you think about it, there were over 80 authors on the Science paper—from multiple institutions, locations and countries—in addition to all the support staff at NASA that helped us do this,” she says. “It was truly a challenging project to complete, and it wouldn’t have been possible without that entire team. That’s how these projects should be done: you bring in expertise from many different areas, think outside the box and piece things together that you would have never thought about unless you were with all those people in the same room.”

With the overarching Science paper out, the Mason Lab has another half dozen publications in progress—continuing to explore what research associate and co-author Daniela Bezdan calls “the most comprehensive and integrated molecular view to date of how a human responds to spaceflight.” For Bezdan and many of her colleagues, just working on a space-related project was a wish come true. The first time she got an e-mail from NASA, she was so excited that she took a screenshot of the header; now, every 10th message in her in-box is from the agency. “We can contribute to making space exploration possible, which could be important for the survival of the human species; it’s something bigger than ourselves,” Bezdan says. “When I think of space travel, I think of three compartments: we are now describing what happens in space; the next step is to understand it—and the third step is to use it for our advantage.”

In Scott Kelly’s 2017 memoir—entitled “Endurance: A Year in Space, a Lifetime of Discovery”—he describes his record-setting tenure on the space station, the longest-duration mission for a NASA astronaut. Toward the end of the book, he contemplates his contribution to the Twins Study, noting that he expects to continue to be a test subject for the rest of his life. “Science is a slow-moving process,” he writes, “and it may be years before any great understanding or breakthrough is reached from the data. Sometimes the questions science asks are answered by other questions. This doesn’t particularly bother me—I will leave the science up to the scientists. For me, it’s worth it to have contributed to advancing human knowledge, even if it’s only a step on a much longer journey.”

This story first appeared in Weill Cornell Medicine, Summer 2019

Weill Cornell Medicine
Office of External Affairs
1300 York Avenue
Box 314
New York, NY 10065 Phone: (646) 962-9476

蜜蜂视频下载app 秀色小抖音app下载 蝶恋花下载app 主播福利下载app 花心社区下载app ML聚合直播下载app 9uuapp下载 红玫瑰直播app下载 health2app下载 金鱼直播app下载 性直播下载app 午夜直播app下载 AVBOBO下载app 秋葵视频下载app 月光直播app下载 成版人音色短视频下载app视频免费最新 春水堂视频下载app 彩色直播下载app 探探直播下载app 陌秀直播app下载 四虎下载app视频免费最新 泡芙视频下载app 探花直播app下载 笔芯直播下载app 盘她app下载 蜜桃直播下载app 烟花直播app下载 猫咪视频下载app 和欢视频app下载 小狐仙视频下载app视频免费最新 菠萝蜜视频app下载 富二代f2下载app 小怪兽下载app 探花直播app下载 樱桃直播下载app fi11含羞草下载app 本色视频app下载 蚪音app下载 食色app下载 后宫视频下载app视频免费最新 香草成视频人下载app 年华直播app下载 丝瓜视频污app下载 男人本色西瓜视频下载app Avbobo下载app 含羞草app下载 小喵直播app下载 左手视频app下载 麻豆传媒直播app下载 葫芦娃下载app 91直播app下载 考拉直播app下载 桃花直播下载app 草榴直播下载app视频免费最新 啪嗒视频下载app 小小影视app下载 番茄社区app下载 番茄社区app下载 大秀直播app下载 男人本色西瓜视频下载app 红娘直播app下载 樱桃直播app下载 微啪下载app 朵朵直播下载app 黄页荔枝app下载 冈本下载app视频免费最新 火辣直播下载app 梦鹿直播下载app 丝瓜下载app 小姐姐直播下载app 七秒鱼直播下载app 小小影视下载app 黄瓜app下载 69热app下载 69视频app下载 花样视频下载app视频免费最新 雨云直播下载app 一对一直播app下载 小米粒直播app下载 小仙女下载app 粉色视频app下载 iavbobo下载app 小小影视app下载 蝶恋花下载app 遇见直播app下载 樱花雨直播下载app 快猫下载app 小猪视频app下载 health2app下载 后宫下载app 圣女直播下载app视频免费最新 桃花app下载 红杏视频下载app视频免费最新 铁牛视频app下载 柚子直播app下载 荔枝视频app下载 香蕉视频app下载 樱花视频下载app 宅男之家app下载 薰衣草直播app下载 红杏视频下载app 樱花下载app 夜遇直播号app下载 黄页荔枝下载app 草鱼app下载 成版人音色短视频app下载 食色短视频下载app 成版人茄子视频app下载 笔芯直播下载app 向日葵视频下载app 卡哇伊下载app视频免费最新 月亮视频下载app 茄子视频下载app 尤蜜视频下载app 豆奶短视频下载app 快猫视频app下载 麻豆传媒app下载 七秒鱼下载app 梦幻直播下载app 千层浪app下载 草榴视频app下载 七秒鱼直播app下载 趣播app下载 柠檬直播下载app视频免费最新 向日葵视频下载app 四虎下载app 雨燕直播app下载 夜夜直播下载app 蜜桃app下载 91香蕉视频下载app 小v视频app下载 水晶直播app下载 铁牛视频app下载 茄子直播下载app 葡萄视频下载app 尤蜜下载app 千层浪视频app下载 薰衣草直播app下载 香蕉app下载 盘他app下载 成版人抖音app下载 番茄视频下载app 草榴视频app下载 千层浪视频app下载 BB直播下载app 泡芙app下载 swag视频下载app 向日葵app下载 内裤直播下载app 福利直播下载app视频免费最新 麻豆视频下载app 兔子直播app下载 小奶狗视频下载app 番茄社区下载app 美岁直播app下载 套路直播下载app 年华直播下载app 番茄直播下载app 富二代f2短视频下载app 豆奶抖音短视频下载app 宅男之家下载app 91香蕉app下载 JOJO直播下载app 柚子直播app下载 蜜桃app下载 奶茶视频app下载 桃花app下载 福利直播app下载 麻豆传媒映画app下载 花样视频下载app 花心直播下载app 蘑菇视频app下载 浪浪视频app下载 成版人短视频下载app 成版人茄子视频下载app 成版人音色短视频下载app 9uuapp下载 抖阴直播下载app 豆奶下载app 香蕉直播app下载 享受直播下载app avgo下载app 宅男之家下载app 夏娃直播app下载 音色短视频app下载 JAV名优馆下载app 月亮视频下载app 小奶狗视频下载app 棉花糖直播下载app 夏娃直播下载app视频免费最新 久草视频app下载 火爆社区下载app 小宝贝直播下载app 老王视频下载app 泡芙下载app 茄子直播app下载 最污直播app下载 菠萝菠萝蜜视频app下载 茶馆视频下载app 七秒鱼直播app下载 富二代f2抖音app下载 梦幻直播app下载 火爆社区app下载 水晶直播app下载 污软件下载app 小猪视频app下载 咪咪直播下载app 玉米视频下载app 梦幻直播app下载 大象视频下载app 玉米视频下载app视频免费最新 圣女直播下载app 福利直播app下载 茄子直播下载app 蜜柚直播app下载 小蝌蚪app下载 火爆社区下载app 花姬直播下载app 嘿嘿连载app下载 直播盒子app下载 豆奶短视频下载app 杏趣直播下载app 斗艳直播app下载 初见直播下载app fi11含羞草下载app 橘子直播下载app 光棍影院下载app 铁牛下载app 成版人抖音app下载 冈本app下载 富二代f2抖音app下载 梦露直播app下载 粉色视频app下载 探探直播app下载 黄鱼视频下载app视频免费最新 香蜜直播app下载 斗艳直播下载app 夜狼直播下载app 黄色直播软件下载app 一对一直播下载app 台湾swagapp下载 蝶恋花下载app视频免费最新 考拉直播app下载 小小影视下载app 心上人直播app下载 成人快手下载app 享爱下载app 柠檬直播下载app 后宫视频app下载 麻豆视频app下载 薰衣草直播下载app 小天仙直播下载app 美梦视频app下载 香蕉直播app下载 草榴直播下载app 樱花下载app 葫芦娃下载app 豆奶短视频下载app 咪哒直播app下载 花姿下载app视频免费最新 蓝颜下载app 杏趣直播app下载 恋夜秀场app下载 杏吧直播app下载 老王视频下载app 小花螺直播下载app 朵朵直播下载app 茶馆视频app下载 逗趣直播app下载 桃花直播下载app 麻豆视频app下载 卡哇伊下载app 快喵app下载 小草视频app下载 卡哇伊app下载 抖阴直播下载app JAV名优馆app下载 番茄直播下载app 妖妖直播下载app 大秀直播app下载 内裤直播下载app视频免费最新 奶茶视频app下载 快喵app下载 花心社区下载app 心上人直播app下载 bobo直播下载app 蓝精灵直播app下载 夜遇直播号app下载 后宫视频下载app 午夜直播下载app 樱桃直播下载app IAVBOBO下载app 小怪兽下载app 7秒鱼直播app下载 美岁直播app下载 快喵下载app AVBOBOapp下载 fi11含羞草app下载 烟花巷app下载 樱桃视频app下载 暖暖直播app下载 花狐狸直播app下载 梦幻直播下载app A头条下载app 米老鼠直播下载app 花友直播app下载 雨燕直播下载app 快狐下载app 色秀直播app下载 左手视频app下载 JAV名优馆下载app 丝瓜视频污app下载 萝卜视频下载app视频免费最新 小宝贝直播下载app视频免费最新 抖阴app下载 蜜柚直播下载app Avnightapp下载 小v视频下载app视频免费最新 夜狼直播下载app 恋人直播app下载 牛牛视频下载app视频免费最新 lutube下载app 花姿直播app下载 音色短视频下载app视频免费最新 丝瓜视频下载app 妖妖直播app下载 豆奶视频下载app 富二代短视频下载app 七仙女直播下载app 荔枝下载app 快猫短视频下载app 雨燕直播app下载 小狐仙下载app 微啪app下载 小草莓下载app 夏娃直播app下载 抖阴直播app下载 金鱼直播下载app 月亮直播app下载 蜜橙视频app下载 夜猫视频app下载 含羞草视频下载app 成版人抖音富二代下载app视频免费最新 丝瓜app下载 奶茶视频下载app 水果视频下载app 梦幻直播下载app 花心社区app下载 9uu下载app 水晶直播app下载 黄鱼视频下载app视频免费最新 青青草app下载 月色直播app下载 可乐视频下载app 泡芙短视频app下载 小仙女app下载 微杏下载app 米老鼠直播app下载 木瓜视频app下载 丝瓜app下载 大番号app下载 猛虎视频app下载 遇见直播下载app 含羞草app下载 小仙女app下载 柚子直播app下载 夜魅直播app下载 乐购直播下载app 烟花巷直播app下载 小狐仙直播下载app 69热app下载 丝瓜视频下载app视频免费最新 福利直播下载app 小公主直播下载app 红玫瑰直播下载app 泡芙短视频下载app 爱爱视频app下载 木瓜app下载 番茄视频app下载 后宫视频下载app 陌秀直播app下载 年轻人片下载app 恋夜秀场下载app 男人本色西瓜视频app下载 黄色直播软件下载app 遇见直播app下载 年轻人片app下载 fi11含羞草app下载 丝瓜视频下载app视频免费最新 比心app下载 小小影视下载app 宅男之家app下载 东京视频下载app 柚子直播app下载 蝶恋花直播下载app 柚子直播app下载 小蝌蚪视频下载app 泡芙短视频app下载 樱桃app下载 色秀直播下载app 月光宝盒直播下载app 快猫视频app下载 浪浪视频app下载 樱花直播下载app 小姐姐直播下载app