Scientists discover ancient DNA that could explain why some people live to be over 100

Wondering how Dick Van Dyke has reached the grand age of 100? Well, a recent discovery on ancient DNA may explain just that.

The veteran actor reached the landmark age on December 13 and has disclosed his secret to living a long life while doing the rounds for his new book, 100 Rules for Living to 100.

And while eating well and exercising on a regular basis can help improve your chances of becoming a centenarian, scientists have found there is a lot more to it than that.

Previous studies have found that 'good genes' from ancestors can go a long way to a healthy life, but experts wanted to delve deeper.

In research published in the journal GeroScience, scientists examined the genomes of 333 centenarians and 690 healthy adults around the age of 50.

Scientists looked into ancient DNA (Getty Stock Image)

Researchers have previously found Italy has one of the highest concentrations of people aged 100+ in the world, so experts in this latest study compared the DNA of the nearly 1,000 people involved to ancient genomes of four groups that make up Italy in 2025.

Ancient groups from the Iranian and Caucasus regions were involved, as well as Anatolian Neolithic farmers and Bronze Age nomadic groups.

The descendants of the inhabitants of Europe following the Ice Age, Western Hunter-Gatherers (WHG), fare the best when it comes to reaching the magic 100 mark.

"The present study shows for the first time that the WHG lineage... contributes to longevity in the Italian population," experts wrote.

Just a small increase in hunter-gatherer DNA saw a person's chance of reaching the age of 100 increasing by a staggering 38 percent.

Meanwhile, women with traces of this DNA were more than two times likely than men to reach 100 years old, scientists found.

Dick Van Dyke turned 100 earlier this month (JC Olivera/Variety via Getty Images)

Experts added in their findings: "We propose that the variants involved in this trait [longevity] may have been introduced into the Italian gene pool at a very ancient time.

"We showed a greater contribution from Western Hunter-Gatherer-related ancestry to Italian centenarians, thus suggesting that this pre-Neolithic genetic component, which has been linked to population shifts occurring within Europe after the Last Glacial Maximum, could be beneficial for longevity today."

It was also found that some of these genes key to longevity could ensure metabolism is working at an optimal level, subsequently processing food more efficiently.

No doubt there'll be more studies looking into the matter in the future.