Researchers publish a reference DNA database for healthy older Australians in an attempt to establish a baseline for healthy aging.
The aging population problem
Owing to the amazing advances made in science and medicine, the elderly population in the world is the highest it has even been in human history. Our life expectancy has increase over time, we are better able to tackle disease, which means we live much longer than our ancestors. However, in the very near future, this same advantage is going to become one of the biggest challenges the healthcare system has faced in the past century – providing proper medical support for our elderly.
According to the WHO (World Health Organization), 22% of the human population will be over the age of 60 by 2050. This means we need to better understand the mechanisms behind aging (especially in terms of our genes), so we can devise approaches to prevent, delay and minimize the risk of diseases that come with age. We want to prepare ourselves today, so we can keep ourselves healthier tomorrow.
This is exactly what the researchers in this study were after – understanding healthy aging as a way to tackle aging diseases. They wanted to get a better idea of DNA changes (genetic variants) linked to certain disease states and aging. By identifying genetic changes relevant to disease, we can use them to predict aging diseases earlier, so preventative measures can be taken and optimal treatment options can be devised.
But, before we can make the link between specific diseases and age, we need to better understand what healthy aging is – essentially establish a baseline for healthy aging. The idea is once you establish which DNA changes are present in a healthy aging population, you can use this as a control to look at how the compare to aging diseases like Alzheimer’s, cardiovascular disease or osteoporosis. By making the DNA connection we can take action early.
Setting up the baseline
This is why we thought this study, which maps out the genome of a healthy, elderly population was very important. These researchers collected DNA samples from 4, 000 healthy older Australians, whose ages ranged from 64-95 years old. One of the criteria used was that they were free from aging diseases like cancer, cardiovascular disease or neurodegenerative disease like Alzheimer’s until at least they were 70 years old.
The Medical Genome Reference Bank (MGRB) at the moment consists of 2, 750 genomes of healthy older Australians, 344 genomes of young people, and 273 genomes of elderly cancer patients. The idea is that this ‘control’ or baseline dataset can now be used to predict the risk of aging diseases, by looking for DNA differences between healthy and disease conditions.
The researchers have already shown that they can predict the genetic-risk of diseases (prostate cancer in this case) with much more power when they use the ‘control’ data from MGRB.
Two measures of aging
When scientists talk about age, they usually refer to our biological age. Biological age is different from chronological age, the number of years a person has been alive. Biological age is a measure of how old your body really is. A number of factors, including changes in your DNA that becomes more pronounced as we age, contribute to our biological age.
Interestingly, our chronological age and biological age do not have to match. If you talk to your doctor you will find out that biological age is a much better measure of your overall health than your chronological age.
This is where establishing ‘normal’ or healthy aging also comes in handy. According to this study, it is possible to even distinguish lifestyle differences like physical activity by just looking DNA, suggesting that genome sequencing can give us a good indication of our biological age. What’s more it can help us monitor people as they age to give them the proper supportive care as early as possible.
You feel young, because you are young!
We believe having the ability to track our biological age with just a simple blood or saliva sample will likely make healthy aging more feasible. The idea is that having the ability to control our disease-risk, whether it is prevention or early intervention, will allow us to get a better handle of aging diseases, lessening the burden on the healthcare system.
What’s more it will give us all an incentive to strive to lower our biological age, so we can stay young, ultimately leading to positive health benefits.
Who wouldn’t want to look young, feel young and actually be young?
The Medical Genome Reference Bank contains whole genome and phenotype data of 2570 healthy elderly