Tampa, Fla .(WFLA) – It’s estimated 12 million people have taken DNA tests through various companies.

During the holidays, many testing companies advertised sales urging people to take a scientific look at where they came from.

A lot of those results may be coming back now.

However, for some people, the results aren’t what they expected Sometimes the results tell deep secrets that have been held for years.

WFLA producer Nancy Ryan took an Ancestry.com DNA test to confirm her Scottish heritage.

“I said to my brothers and sisters, ‘how about I take one and see how much of our dad’s 100 percent Scottish comes out,'” she said.

One night while waiting for those results to come back, she had a terrifying epiphany.

“What if it was something completely different?” Ryan thought.

She was spot on. Her results came back and she is mostly Italian. Neither of her parents, who are both deceased, were of Italian descent.

She learned a deep, dark secret about her parentage.

“The man who raised me wasn’t my father. It was devastating. It was a tremendous loss. It was like he had died again. I loved him,” Ryan said.

What happened to Ryan happens a lot.

People take the tests and wait weeks for the results, only to discover the answer they received was not what they expected.

Another case is Dan Eggleston. He traced his father’s line back hundreds of years. He knew the names of most of his grandfathers. He did that using traditional genealogy methods.

He decided to take a DNA test for confirmation.

“You know, spike the ball. And it was a shock,” he said.

A shock because the results showed his grandfather wasn’t his father’s biological dad.

“My dad was lucky. There was a man there from the moment he was born all throughout his life. That man wasn’t his biological father. Did he know? I don’t know,” he said.

Although a lot of people question the results of DNA tests. Eggleston and Ryan didn’t. They believe in the science.

Drew Smith, an associate librarian at the University of South Florida and a local genealogist, told News Channel 8 people doing these tests need to use traditional research as well.

“These tests are very popular and I think part of it is the advertising,” Smith said.

“We realize DNA testing is the hot, cool thing right now, if I can say that. As a result, it gets people interested to talk about their families. But really the hard work, the work that’s going to take some time, is the traditional research,” Smith said.

Ryan and Eggleston both did the traditional research, never expecting the surprises science handed them. Learning who they are is not who they thought they were.

“It was pretty devastating because I had done a lot of research on that line. A lot,” Eggleston said.

“I was lost a little bit at first. I thought it had to be a mistake,” Ryan said.

“It’s like somebody took a big bite out of your life.”

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