Native Affairs reveal DNA test of full-blooded Maori woman
DNA tests are becoming more accurate, but do have their flaws, says an expert, following a TV show test that showed a woman was "100 per cent Maori".
Maori Television journalist Oriini Kaipara took the test on Native Affairs on Tuesday night. She said she expected it to be about 80 per cent and would have been surprised if it had been less.
"I would have been asking some questions of my mum and dad," she told Stuff on Wednesday.
But Massey University Professor in Computational Biology Murray Cox said it was hard to say exactly what 100 per cent could mean in this context.
Many commercial DNA tests were based in Europe and the United States, which meant the databases were made up of "middle-aged white guys" so there was less data from other parts of the world, such as Asia, Africa, South America, and the Pacific.
He noted that everyone was a mix of DNA, if they traced their ancestry back far enough.
"We're all mixes when it comes down to it."
He explained how the testing worked, saying over time DNA changed, but many of those changes did not do anything such as affect skin colour, or strength, or intelligence, but were often found in particular regions.
Experts could look at an individual's DNA and look for changes, and match them to those found in a particular place.
The weakness in the testing came through a under representation of DNA from Africa, Asia and the Pacific, but as the tests become more popular globally, the data sets were getting bigger and results more accurate.
Kaipara said the results did not change who she was a person, and it did not make her more Maori than anyone else, she said.
There was no way to specifically define what made someone Maori, but there was a whole range of things, and how a person identified themselves.
DNA specialist Brad Argent, who conducted the test, said over time the genetic material that is passed down to a person can by "diluted away".
"In your case ... it's led to you being 100 per cent Maori," Argent said.
"Your brothers and sisters might be different, your parents might be different.
"In broad terms, in the world, we're all becoming a little more mixed it's quite unusual to find anyone pure just one thing.
"Most of us are a mixed bag of everything, and so in some ways you're [Kaipara] kind of unique."
Argent, who is a specialist with ancestry.com pointed out that DNA is just "one tiny part of what makes us who we are".
"We are shaped by the stories of our ancestors, and not necessarily by our genes," he said.
WHAT DID THE TEST REVEAL?
Kaipara, 33, took part in the test for her show. It revealed that she was 98 per cent Maori, or Polynesian.
Argent said her genetic makeup included 1 per cent Scandinavian origins, and 1 per cent Caucasus - the region at the border of Europe and Asia.
Kaipara did not know any ancestors from those areas, and Argent said the two per cent was likely to be "noise" - meaning she effectively had 100 per cent Maori DNA.
However, Kaipara, confessed to knowing she had two Pakeha ancestors.
"I know my whakapapa. I have two English tupuna - one on mum's side, and one on dad's," said Kaipara.