The history of DNA paternity testing

Casey Randall AlphaBiolabs

By Casey Randall, Head of Genetics at AlphaBiolabs
Last reviewed: 18/07/2022

DNA paternity testing is a complex science that uses state-of-the-art technology to verify paternal relationships and provide vital answers for families.

Over the past few decades, DNA technology has advanced to become accessible to all, with mail order DNA testing kits now used daily around the world.  

But did you know that the first paternity tests took place as far back as 100 years ago?

In this article, we look at how a paternity test works, and the history of paternity testing through the decades, from the discovery of blood-type testing and the double helix to DNA profiling.

How does paternity testing work?

Paternity testing works by comparing a child’s DNA profile with that of the alleged father(s).

An AlphaBiolabs paternity test looks at up to 45 DNA markers (loci) – double the industry standard for DNA testing – to identify which half of the baby’s DNA is inherited from the alleged father.

Every person inherits half of their DNA from each of their biological parents, so such a comparison can help us to establish the probability of paternity.

When testing the biological father of the baby, both will share enough sections of DNA at each marker to verify a biological relationship. When the tested man is not the biological father, this will not be the case.

What is paternity testing used for?

Peace of mind paternity tests provide an accurate, cost-effective way of finding out who a child’s biological father is.

In an ideal world, every child would know the identity of both their parents. Sadly, however, this is not always the case.

A peace of mind paternity test can help ensure families get the answers they need. In situations that involve a newborn baby, this can be extremely beneficial, helping remove any doubts and ensuring the father and child relationship gets off to the best possible start.

Delaying the truth can have a huge impact on a child who forms a bond with a man who turns out not to be their father, causing emotional trauma for both parties.

As well as DNA testing for peace of mind, the results of which are for your own personal information, paternity testing can be extremely useful for legal cases, such as child maintenance or custody disputes.

A legally instructed paternity test is performed in exactly the same way as a peace of mind paternity test, but the DNA samples are collected under chain of custody conditions.

This ensures the results of a legal paternity test are admissible in court.

AlphaBiolabs provides legal DNA paternity tests for solicitors, social workers, local authorities, Family Court, specialist immigration solicitors and members of the public.

Paternity testing through the decades

Although paternity testing has a reputation for creating high drama on television, the process of seeking a paternity test is an incredibly emotional and highly sensitive subject for those families who have questions surrounding a child’s parentage.

While it’s usually easy to say who a child’s biological mother is, the question of a child’s paternity can be a different story.

In fact, before the development of genetic profiling in the 1980s, there was no 100% accurate, reliable way of telling who a child’s biological father was using a DNA test.

Early to mid-1900s – blood typing

Many people would be surprised to know that paternity testing originally took place as early as the 1920s, following the discovery of human blood typing.

In 1901, Nobel-prize winning Austrian scientist, Karl Landsteiner, discovered the four distinct blood groups – A, AB, B, and O – while investigating how to complete successful blood transfusions.

As blood types are genetically inherited, this made it possible to analyse DNA and exclude a man as the biological father if the child’s blood type did not match.

It wasn’t absolute proof of paternity, but it provided proof that the father and child were not genetically related in some cases.

In a famous case in the early 1940s, actress Joan Barry took entertainer, Charlie Chaplin, to court, accusing him of fathering her newborn daughter.

The high-profile case featured blood group testing, which was used to definitively exclude Chaplin as the biological father.

1960s-1970s – HLA typing

Genetic paternity testing with greater accuracy arrived in the 1960s, with the advent of human leukocyte antigen (HLA) typing.

Every human being inherits a unique set of these antigens, with half being inherited from the mother and half from the father.

With the introduction of HLA typing, paternity tests could be performed by analysing the genetic material in the white blood cells of the child and comparing them with that of the alleged father.

While these tests were not as accurate as modern paternity tests, as they could not be used to distinguish between alleged fathers who were close relatives, the test results were accurate in around 80% of cases.

1980s – DNA profiling in the 1980s

Even though Watson and Crick first identified the double helix of DNA in 1953, it was only in 1984 that DNA profiling – the backbone of modern-day DNA analysis – became a reality.

In 1984, British geneticist, Sir Alec Jeffreys, developed techniques that are still used today not just to solve crime, but to distinguish between different people’s DNA in the laboratory.

The process of genetic fingerprinting, developed by Jeffreys, involves comparing the lengths of variable sections of repetitive DNA, such as short tandem repeat (STR) markers, between people.

Human DNA sequences differ by 0.1%, meaning that scientists only have a tiny amount to distinguish between individuals.

However, STR markers are highly variable in length between individuals, making DNA testing the most accurate and scientific way to identify someone.

1990s – DNA analysis using PCR

By the 1990s, paternity testing became much more accurate and reliable, thanks to a process called Polymerase Chain Reaction (PCR) testing.

Developed a decade before in the 1980s, the PCR technique made it possible for geneticists to generate millions of copies of STR markers in DNA, to identify matching DNA markers in two or more donor’s DNA samples.

This PCR process is used to perform DNA relationship testing today, including paternity testing.

DNA testing today

Advances in DNA testing over the past 30 years have made the analysis of samples quicker and more reliable.

The move to using cheek (buccal) swabs has further simplified the process as thankfully most DNA relationship tests, except for prenatal paternity tests, no longer require a blood sample.

Nowadays, individuals simply swab the inside of their cheeks to provide a sample of buccal cells for DNA analysis.

DNA relationship testing is also much more affordable and accessible for the public, with paternity tests available to purchase quickly and easily online.

Where can I buy a paternity test?

Thanks to advances in modern science, and continued innovation by DNA testing laboratories like AlphaBiolabs, it’s easier than ever to order a peace of mind paternity test online.

AlphaBiolabs’ non-invasive paternity testing provides the most accurate way of finding out who a child’s biological father is, with only a simple cheek (buccal) swab required.

You can order your paternity test online now for €135. Your secure, password-protected results will be emailed to you the next working day (included in the cost of your test), or the same day for an additional €50.

Got questions about our paternity testing? Call 01 402 9466 to speak to our knowledgeable, discreet Customer Services team, or email info@alphabiolabs.ie.

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