A DNA test says you’ve got Indigenous Australian ancestry. Now what?

File 20180501 135837 1ocfg5o.jpg?ixlib=rb 1.1
Families have secrets – and sometimes we don’t know our complete genetic histories.
from www.shutterstock.com

Elizabeth Watt, Deakin University; Emma Kowal, Deakin University, and Shaun Lehmann

Technologies for amplifying, sequencing and matching DNA have created new opportunities in genomic science. In this series When DNA Talks we look at the ethical and social implications.


Getting your “DNA done” is all the rage in the United States.

The sensationalism started with celebrities such as Jessica Alba, and Snoop Dog – and has now spread to hundreds of video bloggers disclosing their ancestry to drum rolls, exclamations, cheers and tears.

These tests claim to reveal deep ancestral origins, and many public users of this technology are black Americans seeking information about their African roots.

Snoop Dog sent his DNA to be tested – and did the maths faster than this TV host.

The uptake of direct-to-consumer genetic testing has been slower in Australia, and complicated by debates both beyond and within the Indigenous community – with some leaders calling on greater scrutiny to prevent “fakes” or “wannabes” calling themselves Indigenous.

One of the authors on this paper – Shaun Lehmann – was dropped into this debate inadvertently, after receiving the result of his own DNA test a few years ago.




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Professional and personal

Shaun had more professional reasons for doing the test than most: at the time he was lecturing in human genetic diversity at the Australian National University, and wanted to use his own genetic data as teaching tool.

He also had personal questions about his maternal grandmother, who had died when he was a small child. She had grown up without her mother, and said little about her background.

Because they are related through a direct maternal line, Shaun knew that it was his grandmother, and by extension mysterious great-grandmother, who gave him his mitochondrial genome.

Mitochondria are the tiny organelles that make energy in our cells. While the genome in the nucleus of our cells – our 23 pairs of chromosomes – is made up of a mix of our biological mother’s and father’s DNA, the relatively small mitochondrial genome is passed down through the egg and so reflects a single line of maternal ancestors.




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What Shaun didn’t know at the time, and what the test revealed, was that his particular mitochondrial genome fell into a haplogroup (a grouping of similar mitochondrial genomes) called “S2”, which has only been observed in Aboriginal Australians.

Interpreting genetic results

Being mitochondrial DNA, Shaun knew exactly where to look in his genealogy to find out more. Sure enough, he soon found records that his grandmother’s maternal family were Aboriginal people originally from the Albany area of Western Australia. With this information in hand, Shaun was able to trace his family tree to living Noongar relatives.

How mitochondrial DNA and nuclear DNA are passed on.
Wikimedia Commons, CC BY

Shaun’s discovery was certainly aided by the fact that he is a geneticist and could interpret his DNA test results. Most important, though, was that his Aboriginal ancestry happened to be in the direct maternal line.

Mitochondrial DNA is a reliable source of genetic information about Aboriginal ancestry, but it can’t help at all if your Aboriginal ancestors sit anywhere else in your family tree. That is, it’s only useful to track direct from mother to grandmother to great grandmother, and so on.




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Different kinds of DNA tests

Most of the “ethnic breakdown” DNA results being shared publicly by bloggers come from testing companies that compare their nuclear DNA with material from various ethnic groups. The tests focus on variations in specific regions of genes – known as single nucleotide polymorphisms, or SNPs.

To our knowledge, DNA testing companies do not currently have reliable reference SNP data from Indigenous Australians.

One company offering tests claiming to identify Indigenous Australians uses an approach that compares sequences in genes known as Short Tandem Repeats, or STRs. STR data from around the world is widely available in the forensic science literature because it is widely used in criminal investigations and paternity testing.




Read more:
Is your genome really your own? The public and forensic value of DNA


Ethical and scientific concerns have been raised about the use of STR data for commercial ancestry testing. For example, it is difficult to know how companies get their reference samples.

The case of American blogger Lisa Garrigues is illustrative. Garrigues did a test back in 2010 – it reportedly gave her second “Highest Resolution Global Population Match” as “European-Aboriginal”.

She was excited by this discovery, but also sceptical – her family has no known connections to the Southern Hemisphere. Lisa and her father subsequently did more thorough DNA testing, and it didn’t suggest Aboriginal ancestry.

In our personal correspondence with one of the genetic genealogists that assisted Lisa, Doug McDonald suggests these kind of inconsistencies are extremely common – STR markers are not designed for ancestry tests, but for matching individual people.

After the test: now what?

We need to be on the lookout for misinformation and unethical practices around genealogy testing. But even where the science is reliable, such as Shaun’s mitochondrial DNA test, the implications of identifying genetic Indigenous ancestry are far from clear.

Shaun was proud to learn about his ancestry, and has since got in contact with his relatives. He is also looking into his grandmother’s past to find out whether her separation from her mother was influenced by the policies that led to the Stolen Generations.

Existing research suggests there are many possible endings for journeys like Shaun’s. Bindi Bennett’s work highlights how young, light-skinned people who had no previous ties to the Aboriginal community can develop a strong Indigenous identity, even in the face of resistance from that community.




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Culture, not colour, is the heart of Aboriginal identity


But Fiona Noble’s 1996 research with Queenslanders who discovered their Aboriginal ancestry late in life suggests many of this demographic see their heritage as extremely important, but not all-defining.

They are more comfortable describing themselves as being “of Aboriginal descent” than “Aborginal”.

As Regina Ganter notes, the “in-between” status of these “half-steps” is not well-recognised contemporary policy and discourse – which tends to frame Aboriginality as an either/or identity.

Although Noble and Bennett’s research participants discovered their heritage through documents or family stories, not genetics, their work offers a window onto a future where more Australians discover Aboriginal ancestry through DNA tests.

Without a doubt, the inevitable collision of Aboriginal and Torres Strait Islander Australia with direct-to-consumer genetic testing will continue to raise challenging questions about ancestry and identity in the 21st century.


The Conversation


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Elizabeth Watt, Research Fellow, Deakin University; Emma Kowal, Professor of Anthropology, Deakin University, and Shaun Lehmann, PhD Student, Australian National University

This article was originally published on The Conversation. Read the original article.

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Census 2016: what’s changed for Indigenous Australians?


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Australia’s Indigenous population is growing – rapidly.
AAP/Dan Peled

Nicholas Biddle, Australian National University and Francis Markham, Australian National University

Aboriginal and Torres Strait Islander people have a complicated history with the Australian census. Until the 1967 referendum, the question about Indigenous status was used mainly to exclude the Indigenous population from official population statistics, as required by the Constitution at that time.

Since the 1971 Census, however, the question has been used to understand Indigenous demographic and socioeconomic outcomes. This includes observing how Indigenous peoples’ situations are changing through time, and comparing them to the non-Indigenous population.

Indigenous population estimates matter for policymaking. For example, the Commonwealth Grants Commission uses estimates of the Indigenous population to advise on GST revenue allocation to the states and territories. And many Closing the Gap targets are monitored in full or in part using census data.

At the same time, many Indigenous communities and organisations argue that the way data are collected and distributed takes power out of their hands, and puts them at a disadvantage.

So, what did we learn from the most recent release of 2016 Census data?

A rapidly growing population

First, the Indigenous population is growing – rapidly. In data released on Tuesday, it was estimated there are 786,689 Australians who identify as Aboriginal or Torres Strait Islander. This is a 17.4% increase from 2011.

This estimate of the total Indigenous population is based on the 2016 Census, but also takes into account people who were missed in the count. Indigenous Australians are now estimated to represent 3.3% of the total Australian population, up from 3% in 2011.

Setting aside for the moment those who were missed, 649,171 people identified themselves as being “of Aboriginal or Torres Strait Islander origin” in the 2016 Census. This is up 18.4% from 2011.

There are several reasons for the rapidly growing visibility of Indigenous Australians in our population statistics.

The first is the natural increase of the Indigenous population. On average, Indigenous Australians have a slightly higher number of children than non-Indigenous Australians.

In addition, the children resulting from relationships between Indigenous and non-Indigenous Australians often identify as Indigenous, accelerating the growth of the Indigenous population. However, even after taking these factors into account, the Indigenous population was projected to reach no more than 746,815 by 2016 – around 40,000 people fewer than the latest census-based estimate.

While we won’t know how accurate the assumptions underlying these projections were for some time, the probable explanation for the “extra” 40,000 Indigenous people is that some individuals who chose not to identify as Indigenous in 2011 decided to identify as Indigenous in 2016.

The change in propensity to identify as Indigenous makes comparisons over time difficult. Any change in socioeconomic outcomes is likely to partly result from changing life-chances for Indigenous Australians, but is also likely to be partly attributable to the change in the group of people who are classified part of the Indigenous population.

However, because the group of newly identifying Indigenous people is around 5% of the Indigenous population, any change in socioeconomic indicator that is greater than 5% can at least be partly attributed to a change in the circumstances of the families who identified as Indigenous in 2011.

Population geography

Regardless of what factors drove Indigenous population growth in the 2016 Census, it is clear that population growth was not evenly distributed.

As the map below of the change in census counts between 2011 and 2016 shows, the Indigenous population increased by the greatest amount in Brisbane, on the New South Wales central and north coast, and Sydney – Wollongong. Almost half (49%) of the growth of the Indigenous population occurred in just these three regions.

Conversely, the Indigenous population of the East Kimberley, Alice Springs, and several other remote regions appeared to decline slightly.

These initial figures should be interpreted cautiously. The proportion of records for whom we do not have an answer to the Indigenous status question on the census increased by about one-third between censuses. Nevertheless, it is clear that Indigenous population growth remains concentrated in NSW and Queensland.

Indigenous population change by region.
Census 2016

The changing distribution of the Indigenous population can be better understood through a cartogram, as in the figure below. Each circle represents a location defined by the Australian Bureau of Statistics as an “Indigenous Area”. The circles representing these locations have been sized so that their areas are proportionate to their Indigenous population count in 2011.

They have been moved on the map so they do not overlap, but under the constraint that they move as little as possible, that they remain within their state boundaries (except for the ACT), and that they retain their relative position next to each other as much as possible.

We have also added a line around the greater capital city areas to help readers identify them. Each area has been coloured in a manner that indicates the change in population between 2011 and 2016.

Indigenous population change by area.
Census 2016/Authors

What the cartogram shows very clearly is that in 2011, the Indigenous population was already highly concentrated in coastal NSW and Queensland. The cartogram suggests the Indigenous population has grown substantially everywhere in the greater Brisbane/Gold Coast region, in much of the NSW central and north coast, and around the fringes of Greater Sydney and Greater Melbourne.

The places where the Indigenous population declined tend to be locations that had a low population in 2011 and that are located in remote parts of Australia. However, there are plenty of exceptions to both of these general patterns.

Language

In 2016, the number of people speaking an Australian Indigenous language at home increased by a small amount – to 63,754 persons from 60,550 in 2011.

This was an absolute increase. But it represents a decline in the proportion speaking an Australian Indigenous language – from 11.8% in 2011 to 10.5% in 2016.

This proportionate decline may result from Indigenous population growth being concentrated in areas where Indigenous languages are less commonly spoken. So, it would be hasty to jump to the conclusion that these results suggest language loss.

Education

Indigenous people are getting into the education system earlier and staying for longer. This is likely to lead to improved socioeconomic outcomes in future.

Early childhood education rates have increased. The percentage of three-to-five-year-olds who aren’t already at primary school that were attending preschool is up from 43.5% in 2011 to 48.5% in 2016.

At the secondary school level, 59.7% of Indigenous people aged 15-18 were attending school. This is up substantially from 51.2% in 2011.

Increased school attendance has flowed through to growth in the percentage of Indigenous people aged 15 or more who have completed year 12. This rose to 34.6% in 2016 from 28% in 2011.

Finally, the proportion of Indigenous 15-24-year-olds undertaking tertiary education appears also to have grown. In 2016, 16.2% of this cohort who were not at secondary school were studying for a tertiary qualification. This is up from 14.1% in 2011.

Significantly, this growth has been driven by increased university attendance (8.5% in 2016, up from 5.8% in 2011). Attendance at technical or further educational institutions has actually been falling (7.7% in 2016, down from 8.4% in 2011). This shift from technical education to university education is suggestive of the continued growth of an Indigenous middle class.

Income

Indigenous people are also earning more on average in 2016 than 2011.

Real median weekly personal pre-tax income is up from A$397 in 2011 to A$441 in 2016. Although incomes grew generally between censuses, the growth in incomes for Indigenous people outpaced that of the rest of the population. Nevertheless, on average, Indigenous people still receive a personal income that is only two-thirds that of the non-Indigenous population.

Similar trends were evident for household income: Indigenous household incomes are increasing more rapidly than non-Indigenous household incomes.

Housing

Similarly, home ownership rates among households with at least one Indigenous resident have increased slightly, from 37.4% to 39.6%.

Households with a resident who identifies as Indigenous are also slightly less likely to be overcrowded than in the past. The proportion of households in a house that doesn’t meet the international standard for overcrowding from 11.8% to 10.4%.

At the same time, overcrowding by the same measure among non-Indigenous households has risen between 2011 and 2016, from 3.2% to 3.6%.

Tempered optimism

The 2016 Census has mostly delivered a good news story in terms of Indigenous outcomes. But the extent to which these positive results indicate that life is getting better for Indigenous families remains unclear.

At least some of these apparent improvements are likely to be the result of people of relatively high socioeconomic status identifying as Indigenous for the first time.

In addition, there were a number of census records for which we know nothing about whether the person is Indigenous – around 6% of the total count. This is because these people didn’t fill out any census form, or they didn’t answer the Indigenous status question. Either way, we need to keep this uncertainty in mind when interpreting findings.

The ConversationAnd while we have generally presented national figures here, socioeconomic outcomes for Indigenous people vary dramatically across Australia. Overall improvements, while welcome, may well mask less positive outcomes in specific regions.

Nicholas Biddle, Associate Professor, ANU College of Arts and Social Sciences, Australian National University and Francis Markham, Research Fellow, College of Arts and Social Sciences, Australian National University

This article was originally published on The Conversation. Read the original article.