Epigenetics: How environment can alter genes for generations
Tucked away in an isolated area of northern Sweden, there is a collection of small villages known as Överkalix. The region is home to people who can trace their ancestors back to the 15th century when the area was first settled.
One descendent is Lars Olov Bygren, a researcher at Sweden’s Karolinska Institute. His interest in the lifelong effects of nutrition led to some fascinating research that followed Överkalix residents across generations, proving environmental conditions can permanently change gene expression.
The research joins a growing body of work in a field known as epigenetics. This is the study of inherited changes to gene expression, while the underlying DNA sequence remains unchanged. It means that individual lifestyle and environment can “turn on” or “turn off” genes in later years, or even in later generations. Or as Bygren has described it, “early influences that give late replies.”
Back to Sweden: Överkalix villagers depended on a good harvest every summer to make it through the long, dark Scandinavian winters. Some years were better than others, and Byrgen’s team of researchers wanted to analyze the effects of feast or famine over time. Given the abundance of community records, and the relatively genetically isolated nature of the region, Överkalix was a perfect subject for research.
They tracked about 100 males born in 1905 across generations, and found a startling correlation with the participants’ grandfathers. Bygren’s research found that grandsons of men who experienced a famine season just before puberty had a longer life expectancy than the grandsons of men who lived in times of plenty just before puberty. The difference in the grandsons’ average lifespan was an astonishing 32 years.
The findings show that the nutritional environment doesn’t just affect the current generation, but can in fact be handed down. It begs the question: Are there other life choices we’re making that will affect the genetic expressions of future generations? Early epigenetic research would suggest it does.
It’s yet another reason we cannot fall for the myth of genetic destiny. What we inherit from our parents, grandparents – and even ancestors – is not a simple one-plus-one-equals-two formula. Genomic information is complex and science continues to discover new layers and nuances every year.
When we talk about genomics today, we’re thinking about the exome being expressed and making a protein. The other 98% that doesn’t express itself in protein should not be ignored; there is a lot of information in that portion.
Because there’s much to still learn in fields like epigenetics, point-of-care genomic solutions must have placeholders for these larger concepts. We’ve built the 2bPrecise platform to handle this level of complexity. It’s ready to help clinicians navigate the ever-growing knowledge base of genomic medicine today and in the future.