In April 2018, genetic genealogy helped solve the case of the ‘Golden State Killer’, behind at least 50 rapes, 13 murders and 100 burglaries in California, US, committed over a decade in the 1970s and 1980s. How did they do it? Authorities used DNA samples collected on the scene, a free genealogy and DNA database called GEDMatch, and a simple family tree.

The question about where we come from has fascinated humans for centuries: long before written records, oral stories passed from one generation to another served as a window into our beginnings, a fragile thread between people. Genealogy, which comes from two Greek words, genea “race” or  “family” and -logia, “theory” or “science,” the study of someone’s lineage, formalised the ancestral process.

Anne Lehmkuhl is a South African genealogist and history researcher who has been involved since 1986; she was involved on two episodes of Who Do You Think You Are?, a BBC documentary about celebrities’ ancestry, and participated in an Al Jazeera English documentary – People and Power: Colours. 

“I’ve seen [genealogy’s] popularity grow over the years, especially once the internet became more accessible in South Africa. The main audience used to be older people, usually in their retirement years, but since schools started including a lesson that asks learners to do their basic family tree, it has reached younger people by making them inquisitive about who their ancestors were,” she says. 

Lehmkuhl gets about 15 requests per week, usually sparked by curiosity. “It used to be curiosity about their ancestors, a child’s school project, or events around Heritage Day; but in the last two to three years a lot of requests received are from people who want to find a foreign-born ancestor to claim an ancestry visa overseas.”

Finding information about one’s lineage – without using DNA testing – depends on what the person already knows and what information can be found in the national archives and local records.

Lehmkuhl notes that the more a person knows about their ancestors (like dates and places of birth and death or family names), the better it is to help locate records and build family trees. Yet, there can be issues with records, even though the Department of Home Affairs has archives “going back to the very early 1900s when civil registration laws came into effect”. 

Records that are not indexed, or that are filed under a town district which could be different to the person’s usual place of residence at the time can be “like finding a needle in a haystack,” she says. And then, there are also restrictions on civil registration records (30 years for a death register and 100 years for a birth register) that make access to registers very difficult.

“In the last five years or so, the Department of Home Affairs has made it extremely difficult for someone to get a birth, marriage, or death certificate if you do not provide a 13-digit ID number… But these numbers only came into being in the late 1970s, so someone who was born or died before that is very difficult to trace in their system. Nowadays, their answer is that the ‘information is not in our system.’ This is not only a problem for tracing family history, but also for older people trying to apply for a state pension or grant.”

This is where DNA testing can help; US genealogist and consulting forensic genealogist Melinde Lutz Byrne points out that, “People can have a question about every facet of their life that could be affected by genealogical answers. Usually, a rite of passage like a birth, marriage, or death can generate interest and questions. Soldiers in World War II encountered people from all over the world who had the same surname and became interested in the relationships this suggested. 

“A friend of mine in Mongolia wants to know her mother’s ancestry – mother was sold at 14 to an old man for four camels in the Gobi. She ran away to Mongolia’s one large city, Ulaanbaatar, married and had three children, then died when they were all very young… With the addition of DNA evidence, this can be done for almost everyone back through history in certain lines. Where gaps in paper records once stopped research, DNA can help build bridges.

“Not everyone wants to work backwards, though – many are interested in working laterally – cousins to great distances, like the Six Degrees of Kevin Bacon.” Every story is unique and every case exceptional, but Byrne says that often “the circumstances, the context, the solution” can all be incredible.

“For instance, a man in his forties discovers a one-night stand 18 years ago resulted in a daughter and although he doubts it, he pays for her college education and supports her, and presents her to his parents who, despite having three children, had no grandchildren but this girl. The girl later invites the man to take a DNA test so she can know more about her ethnicity. She turns out not to be his daughter, after all. 

“The man’s father, on his deathbed, calls each of his three children in and tells the man that he is adopted. The story of his abandonment by his biological dad and the adoptive dad’s theft and hiding of the baby from the biological mother who has never given up looking for him, are a shock. The man realises that in his whole life he has never met anyone to whom he was related. Not his daughter, his father, his mother, or his sisters. He is a well-known articulate performer and his expression of these feelings is worthy of a book. They are all like that…” she says.

Not all family findings are positive ones and digging up one’s ancestry can have shattering results. Lehmkuhl says that the most startling is when records show that a person’s death was by murder by a family member, and no one spoke about it.

A story published in the Atlantic reports that “DNA tests that unearthed affairs, secret pregnancies, quietly buried incidents of rape and incest, and fertility doctors using their own sperm to inseminate patients” are not unusual either.

Recently, the combination of DNA testing and family tree sleuthing has also led to staggering results in solving crimes, some dating back decades ago.

For 42 years, authorities tracked down the “Golden State Killer” with no success; but in 2018, using DNA samples collected on the scene, and GEDMatch, a free DNA database and genealogy website based in Lake Worth, Florida, they finally had a match. On April 24, 2018, they charged 72-year-old Joseph James DeAngelo, a Vietnam veteran and former police officer, on suspicion of being the man behind the murders.

The case gripped the US, not only because it allegedly ended the desperate hunt for a serial killer, but also because it used one of the largest databases of human DNA, tracing a path to the suspect one DNA match at a time. 

The woman who helped solve the case, Dr Barbara Rae-Venter, is an expert in genetic sleuthing techniques. She and her team use DNA left on a crime scene and DNA information uploaded on public databases to look for possible matches. Although the method might seem laborious, using DNA data and a simple family tree can help you trace a path to a suspect quite effectively. The irony is, although a suspect might have never uploaded DNA information on one of the public databases, someone from their family – even a distant cousin – might have. And that would be enough to close the gap.

Public (and free) DNA databases have grown exponentially in the last few years – in early 2019, “more than 26 million consumers had added their DNA to four leading commercial ancestry and health databases”, according to the MIT Technology Review. “If the pace continues, the gene troves could hold data on the genetic makeup of more than 100 million people within 24 months,” adds the author, Antonio Regalado.

The reasons behind such fervour? Anything from curiosity about genetic origins, to a search for relatives or health concerns. Byrne explains that, “DNA testing is an integral part of both unlocking medical knowledge or establishing family relationships. It can confirm or refute a paper-based or hearsay solution. It can also show that something long accepted is incorrect and that something unsuspected is true.”

Personalised DNA-testing is also said to give clues on someone’s health status: from what kind of exercise or diet might work best to which genetic disease you might be prone to.

There’s a bunch of private DNA-testing agencies online that will test your DNA for a fee; in South Africa DNA tests cost anything from R3,295 (easydna.co.za) to R4,500 for the Ancestry by DNA option (dnatest.co.za). Genetic tests are usually done using a sample of blood, hair, skin, or other bodily fluid. The sample is then sent to a laboratory where it will be digitised; algorithms compare the nucleic acid sequence with a reference population’s, at up to over 7,000 locations, to see where pieces of your DNA possibly come from.

Although the method can be effective for individualised research, for broader searches, like finding from which geographic regions your DNA originates, the process, which only looks at a fraction of your DNA, is only as good as the libraries or reference populations your sample will be compared to – and each library might have different reference populations, giving completely different results.

Then, there are the rising concerns about DNA data privacy. But Byrne notes that, “For most, you upload test kit results. Utilities specific to the database compare it to the data of other uploads. In all cases I know of, you only see the data that is shared with your upload – so if a person is a fifth cousin and you share a 10 centimorgan (cM) segment on one chromosome, you just see 10cM of the 750,000 single-nucleotide polymorphisms (SNPs) being compared in each kit. This is a common result. How this is a risk to anyone is beyond me. Most people don’t know what a centimorgan is, and if there is a use for knowing about a random 10cM, I don’t know what it might be.”

She may have a point. Reading about what a centimorgan is (as well as a single-nucleotide polymorphism), can be an obscure exercise for anyone not trained in genetics.

The National Human Genome Research Institute explains that the centimorgan “is named after a US geneticist named Thomas Hunt Morgan. He worked on fruit flies, and he defined the capacity of one part of a genome to separate from another in going from one generation to another. And that’s important, because in every generation chromosomes exchange pieces of information, and that’s called recombination. And that’s important for introducing genetic diversity into the population. And it was necessary to define a rate at which this happens, and so that’s where this term centimorgan comes from.”

Still confused? The concept of centimorgans is undeniably complex and not easy to grasp, yet many have voiced their concerns over public databases like GEDMatch or Ancestry.com or closer to home, EasyDNA, handling one’s personal genetic data and possibly sharing it with third parties, be they insurance companies, or law enforcement agencies. Or even worse, the risk that these databases get hacked, with personal and confidential genetic information being used or shared.

Byrne warns: “Once something hits the internet, it is no longer private. Period. That includes financial, medical, religious, every kind of potentially private data. Genetic privacy is a fiction – you leave your genetic information on everything you touch, you share your genetic information with everyone you’re even distantly related to. Can you harm people with the genetic information of others? Definitely. Can they harm you? Definitely. How you behave with someone’s genetic information should be no different from how you behave with someone’s other personal data.”

The Academy of Science of South Africa (ASSAf) published a report in November 2018, advising the South African government to update its policies and regulations, stressing that “Direct-to-consumer genetic marketing and testing must be regulated”.

The authors – a panel of 13 members, professors and doctors from SA universities – pointed out that “legislation in South Africa that deals with genetics and genomics is very limited” and that the need for better regulations, based on Ubuntu, “a philosophical notion that refers to the essence or quality of being human”, as well as the creation of a national Human Genetics Advisory Board were fundamental.

The panel also noted: “It is important to recognise that asymmetrical power relationships in science and medicine, together with historically unfair exploitation and data mining in Africa, especially where genetics and genomics are concerned, are important precursors to the ethical, social and legal dilemmas that exist in this field today.”

The report added: “From the moment of conception, deoxyribonucleic acid (DNA) dictates the nature of the structural and functional components that, once fully integrated, define who and what we are. Also contained within DNA is information that may indicate our predisposition to certain diseases, our potential to benefit from certain therapeutic drugs, and our ability to integrate into and function within the environment in which we live.

“While this information can be used to maintain health, and manage disease for an individual or groups of people, it can also be misused and result in consequences that are detrimental”. 

DNA defines who and what we are; it is the essence of our very being. And as such, it might be the one bit of information we want to keep confidential.

As Abraham Lincoln said, “I don’t know who my grandfather was; I am much more concerned to know what his grandson will be.” ML

In other news…

South Africa is in a very real battle. A political fight where terms such as truth and democracy can seem more of a suggestion as opposed to a necessity.

On one side of the battle are those openly willing to undermine the sovereignty of a democratic society, completely disregarding the weight and power of the oaths declared when they took office. If their mission was to decrease society’s trust in government – mission accomplished.

And on the other side are those who believe in the ethos of a country whose constitution was once declared the most progressive in the world. The hope that truth, justice and accountability in politics, business and society is not simply fairy tale dust sprinkled in great electoral speeches; but rather a cause that needs to be intentionally acted upon every day.

However, it would be an offensive oversight not to acknowledge that right there on the front lines, alongside whistleblowers and civil society, stand the journalists. Armed with only their determination to inform society and defend the truth, caught in the crossfire of shots fired from both sides.

If you believe in supporting the cause and the work of Daily Maverick then take your position on the battleground and sign up to Maverick Insider today.

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