Genetics plays a role in the overall health and well-being of humans. Genes provide instructions for making proteins, which help determine the structure and function of each cell in the body. Aside from determining the characteristics inherited, genes have been linked to many diseases. Scientists have determined the genetic information of health.
A team of researchers aimed to better understand the disease process and the role of genes in disease development. To do this, they need to study the genomics of health, or how these genes influence what keeps us healthy.
For the first time, the team, who were from the Garvan Institute of Medical Research, collated a genome reference of thousands of healthy Australians, who were between 64 and 95 years old. The study may help predict gene variants more accurately than methods in the past.
The findings of the study, published in the journal Nature Communications, included the first 2,570 genomes of the Medical Genome Reference Bank (MGRD), which is a combination of two studies, the ASPREE study and the Sax Institute’s 45 and Up Study.
With a comprehensive analysis of healthy people, the researchers were able to provide a clear understanding of which genes are linked to disease, and which are not. The researchers believe that the MGRB will give a good and ideal baseline for genomic studies in the future.
Billions of DNA letters in the genome
No two persons are alike, and the same is true when it comes to their genetic makeup. Every individual has about 6 billion DNA letters encoded in their genome, which are tied to all the information vital for cellular processes in the body. In fact, between two unrelated individuals, there are millions of single-letter variations or differences.
These variations in the genome make people unique and different, but some of these differences can lead to disease. Hence, the researchers wanted to identify which genes make people sick and which do not.
By studying about 2,570 healthy adults in Australia, who were free from diseases such as neurodegenerative disease, cardiovascular disease, and cancer until the age of at least 70, the researchers have a new baseline and a more statistically powerful framework to identify disease-causing gene variants.
For example, the team studied genomes of prostate cancer patients and discovered that by using the MGRB as a control, it provided a 25-percent higher predictive power of disease-linked gene variants, than other genome databases.
Detecting genetic changes linked to aging
The researchers used whole-genome sequencing to determine the biological age from DNA and to detect changes tied to aging, such as less mitochondrial DNA, caps at the end of chromosomes, or having shorter telomeres.
The amount of mitochondrial DNA, which codes for the energy generators of cells, has been linked to higher grip strength in men. The scientists were able to find certain genome changes that could distinguish between healthy older adults that share the same age but have varying physical function. The findings of the study hint that the DNA in a person’s blood sample may provide a marker for their biological age than their chronological age.
“The ability to derive a measure of biological age may better predict health outcomes for individuals. As our population ages, understanding the genetic basis for healthy aging will become more and more important," Professor David Thomas, Garvan Cancer Research Theme Leader and Director of The Kinghorn Cancer Centre, said.
The MGRB will contain genomic information from more than 4,000 older adults in Australia once it’s completed.
Pinese, M., Lacaze, P., Rath, E.M. et al. The Medical Genome Reference Bank contains whole genome and phenotype data of 2570 healthy elderly. Nat Commun 11, 435 (2020). https://doi.org/10.1038/s41467-019-14079-0, https://www.nature.com/articles/s41467-019-14079-0