Yes. A new study confirms that epigenetic changes pass down through multiple generations. These are shifts in how genes are used (expressed), not changes in the genes themselves. That matters. Metabolic disorders and neurodegenerative (brain-wasting) conditions keep rising with each generation. Yet human genes have barely changed.
Diseases you cannot catch, like metabolic and brain-wasting disorders, have been rising with each generation. Studies show that human genes have not changed much in the last few generations. But gene expression has changed. Epigenetics is the study of these changes in gene expression. A new study shows that such epigenetic gene changes can also be passed down to multiple generations.
For a long time, medicine has known two big risk factors for disease. One is genetics. The other is the environment, including lifestyle choices. So, for years, doctors believed most diseases strike people who have a genetic weak spot and then meet a trigger in the world around them. Those triggers include infections, toxins, diet and so on.
So, in people with a genetic weak spot, bad food choices and obesity lead to diabetes. In the same way, metabolic disorders, toxins and infections raise the risk of autoimmune diseases, dementia, and even many kinds of cancer. Still, these theories fail to explain the rise of certain health conditions. So researchers thought there must be something more. Something they still fail to understand.
They noticed that many people have become prone to brain-wasting disorders, obesity, diabetes, heart disease and cancer. Their bodies seem unable to cope with these health problems. It appears as if some genetic changes have occurred in the population. But geneticists say there is no evidence that human genes have changed significantly in the last century.
Still, health experts noticed something. Human genes have not changed significantly in the last few decades, but gene behavior has. More exactly, gene expression has changed. Some gene parts became more active and others less active. That explains why people have become prone to certain health disorders in the last century.
It appears these changes in gene expression came from fast changes in how we live and the world around us. For example, people sit more and eat more processed foods. When lifestyle or the world around us changes gene expression, that is called an epigenetic change.
Epigenetics gave researchers a new tool. For the first time, they could explain why certain groups of people have become prone to specific health problems. But here is the worrying part. These epigenetic changes can also be inherited. So coming generations are becoming prone to metabolic disorders. The cause is inherited changes in gene expression, even though gene structure has not changed significantly.
The theory that epigenetic changes can be inherited still has to be fully proven. Most evidence so far comes from observation rather than firm proof. But things are changing fast. More and more studies are proving the idea that epigenetic changes can be inherited.
The latest study was published in the journal Proceedings of the National Academy of Sciences (PNAS). Researchers focused on one epigenetic mark (called H3K27me3). This mark is known to switch off (repress) the genes it sits on. The team studied the nematode worm C. elegans. They showed that epigenetic marks were passed on even to the third generation of the worms.
It means bad lifestyle habits, like binge eating and sitting all day, can change gene expression. These epigenetic changes can then pass to the next generation. Once children or grandchildren inherit these epigenetic changes, they face an even greater risk of metabolic disorder. It also means that healthy lifestyle changes can make healthy epigenetic changes and ensure healthy offspring.
So people living with a harmful lifestyle need to understand this. They are not only harming their own health. They are also raising the risk of certain health conditions for coming generations.
Frequently asked questions
What is the difference between a genetic change and an epigenetic change?
A genetic change alters the gene itself. An epigenetic change leaves the gene alone and changes how it is expressed, turning some parts up and others down. Geneticists find no evidence that human genes have changed much in the last century. Yet gene expression has. That shift helps explain why so many people are now prone to obesity, diabetes, heart disease and dementia.
What causes epigenetic changes?
Lifestyle and environment. People now live very differently. They sit more, eat more processed food and binge eat. That shifts which parts of genes are active and which are quiet. Researchers call those shifts in gene expression epigenetic changes. They help explain why certain groups of people have become prone to specific metabolic and brain diseases while their genes stayed the same.
Can epigenetic changes be inherited in humans?
The evidence points that way, but it is not fully proven in people yet. Most human evidence so far comes from observation rather than firm proof. What has changed is the lab work. A growing number of studies now show epigenetic marks passing from parent to offspring. The latest shows them lasting to the third generation in an animal model.
What is an example of epigenetic inheritance?
The study in this article is one. Researchers published it in the Proceedings of the National Academy of Sciences. They followed an epigenetic mark called H3K27me3, which switches off the genes it sits on, in the nematode worm C. elegans. The mark was still being passed down in the third generation of worms, long after the first change was made.
Can epigenetic changes be reversed?
The same mechanism runs in both directions. Binge eating and a sedentary life can change gene expression and hand that change to children and grandchildren. If so, healthy lifestyle changes can make healthy epigenetic changes too. That is the practical point of this research. The choices you make now shape your own risk and the metabolic risk your children inherit.
Dr. Gurpreet Singh Padda, MD, MBA, MHP
