Twin Study in Space

Twin Study in Space

One of the most exciting experiments conducted on the Space Station has been the twin study in space. Mark and Scott Kelly are identical twins, and both are astronauts. Scott lived aboard the International Space Station for a year. Mark remained on Earth and lived his normal lifestyle. Both men took daily blood and urine samples so that scientists could evaluate any changes caused by living in space.

Life aboard the space station is very regimented and very different from Scott’s previous life on Earth. On the Space Station, fluids swelled around Scott’s upper body and head, his immune system worked overtime, and his metabolism was altered. Of greatest interest to scientists was that Scott’s genetic makeup – his DNA – had been damaged.

There are protective structures called “telomeres” at the ends of our chromosomes. These structures get shorter with age and put the person more at risk for age-related illnesses. In Scott’s case, the telomeres temporarily lengthened and then became shorter. This means that space flight could put the body at risk for age-related conditions such as heart disease and cancer.

In addition to the changes in the telomeres, there were other changes in Scott’s health. His eye shape changed, and his vision weakened. His cognitive speed also decreased. Scott’s risk of heart disease measurably increased.

What conclusion can we draw from the data of the twin study in space? First, the human body was designed for living on planet Earth. Even a small change in environmental characteristics can make genetic changes that can be detrimental to human health.

The experiment also shows useful facts about the human body. The effect of telomeres is interesting and may explain the changes in humans’ life expectancy in the past. The importance of taking care of the world in which we live is also apparent from this data. We can clearly see that God designed this planet for humans to live. We will have challenges if we start traveling great distances into space in the future.

— John N. Clayton © 2021

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