DNA Day 2024

Let’s take a look at some of the advancements through the decades of the last hundred years, and some of the names - both well known and more obscure - that have played a key part in those remarkable breakthroughs.

1900s

The 1900s kicked off what would later be dubbed “The Century of the Gene” in spectacular fashion.

The work of Gregor Mendel on the principles of inheritance was rediscovered not just once, but four times by different researchers working independently on the principles of inheritance - Dutch botanist Hugo de Vries, German botanist Carl Correns, and Austrian agronomist Erich von Tschermak all made the discovery in 1900, with American economist William Jasper Spillman joining them a little later, in 1901.

In 1902, the Boveri-Sutton chromosome theory of heredity was published, positing that genes are always found at the same specific points along a chromosome, and that this affects their behaviour during meiosis. This behaviour helped to explain Mendel’s laws of inheritance.

1910s

In 1909 Phoebus Levene had published his tetranucleotide hypothesis, proposing that chromosomes were composed of equal amounts of adenine, guanine, cytosine, and thymine. He coined the name ‘nucleotide’ for the phosphate - sugar - base unit.

In 1915, Thomas Hunt Morgan, Alfred Sturtevant, Calvin Bridges and Hermann Joseph Muller published The Mechanism of Mendelian Heredity which contained Morgan’s theory of the chromosome, developed during his work with fruit flies, definitively linking trait inheritance to specific chromosomes.

1920s

The fantastically named Theophilius Painter was the first person to count how many chromosomes humans have - although he miscounted and claimed we have 48 rather than the actual 46. His error was taken as fact all the way up until 1956.

Following his tetranucleotide hypothesis almost two decades earlier, Phoebus Levene discovered deoxyribose - the D in DNA - in 1928. He eventually published more than 700 papers and articles during the span of his 50 year career.

1930s

In 1931, during her research as part of her Ph.D, Harriet B. Creighton and her Ph.D supervisor Barbara McClintock published a paper describing the process of chromosomal crossover - the exchange of genetic material that happens at the point of conception. While this process had been theorised by Thomas Hunt-Morgan years previously, Creighton and McClintock were the first to be able to prove how this happens.

1940s

Many had, until 1944, assumed that the protein component of chromosomes was the carrier of genes, but Oswald Avery, Colin MacLeod, and Maclyn McCarty were able to prove that it’s nucleic acid that contains the key information.

1950s

Cleargraff was one of the first to fully grasp the gravity of Avery et al’s findings. He built upon Levene’s work on tetranucleotides to examine the DNA of different species, and published Chargraff’s Rules in 1950.

In 1952, Rosalind Franklin and Raymond Gosling captured Photo 51 of crystals of DNA B (hydrated). This now infamous photo clearly showed the helical structure of DNA for the first time.

The following year, Pauling proposed that DNA was a triple-helix, with bases on the outside. He didn’t have the advantage of having seen Franklin’s work, but Watson and Crick had been shown the images (by a 3rd party, without her knowledge or permission), and, on the 25th of April 1953, they published in the journal Nature proposing a double-helix with a sugar-phosphate chain and bases paired inwards.

Later in the ‘50s, Crick went on to propose that DNA sequences are translated into proteins, and in 1958 Gamow and Brenner proposed that groups of 3 bases code for the 20 amino acids in proteins.

1960s

In 1961, Marshall Nirenberg made a groundbreaking discovery, showing that an RNA codon, or triplet, is converted into an amino acid, unravelling a key aspect of the genetic code. This laid the groundwork for further understanding the relationship between DNA, RNA, and protein.

Just 5 years later in 1966, the genetic code was deciphered. This breakthrough was achieved through the collaborative efforts of many scientists working worldwide.

1970s

In 1977, Fred Sanger revolutionised the field of genetics by designing the first rapid sequencing method, known as the Sanger sequencing technique. Sanger’s groundbreaking innovation led to even more advancements in genomics and revolutionised biomedical research.

1980s

Kary Mullis developed the PCR (polymerase chain reaction) in 1983. This technique amplifies DNA segments exponentially, enabling the rapid and precise replication of specific DNA sequences. PCR has become an indispensable tool in genetics research, diagnostics, forensic analysis, and biotechnology.

In 1984, a groundbreaking study at the University of California, Berkeley, proved the feasibility of extracting and analysing genetic material from ancient specimens by extracting traces of DNA from a 150 year old museum specimen of a quagga (an extinct subspecies of Plains Zebra).

Automated DNA sequencing technology was introduced to the market for the first time in 1986, making faster and more accurate DNA sequencing more accessible than ever before. This commercialisation of DNA sequencing paved the way for widespread use of sequencing technologies across a number of scientific fields.

1990s

In 1990, the Human Genome Project was launched with the monumental aim of mapping and sequencing the entire human genome in just 15 years. Led by an international team of researchers, the HGP was a collaborative effort on an unprecedented scale.

Scientific history was made in 1996 with the birth of Dolly the Sheep - the world’s first mammal cloned from an adult somatic cell. Dolly’s creation at the Roslin Institute in Scotland sparked widespread debate and raised ethical concerns about the implications of cloning technology.

John Craig Venter announced a partnership with Applied Biosciences in 1998, with the aim to sequence the human genome in just 3 years and at a fraction of the cost of the HGP. He planned to do this using shotgun sequencing, which had been rejected by the HGP due to concerns over its accuracy. With this commercial competition however, the HGP also moved to shotgun sequencing which both sped up the research and reduced the overall cost.

2000s

With the change in methodology and added assistance from Venter and his project, the Human Genome Project steamed ahead, with the first draft being published in 2001. This monumental achievement, resulting from the collaboration between the international Human Genome Project and the private sector, came years ahead of schedule.

Just 2 years later, on the 25th of April 2003, the scientific community celebrated the completion of the Human Genome Project. After more than a decade of collaboration, the project’s completion marked the successful sequencing of the entire human genome, comprising approximately three million base pairs of DNA.

In 2004, Professor Sir Walter Bodmer launched the People of the British Isles (PoBI), a population genetics project which is based at Oxford University and aims to create a detailed genetic map of the country.

2010s

Using a mechanism found naturally only in bacteria, which takes a copy of viral DNA and incorporates it into the genome of the bacteria itself, Emmanuelle Charpentier and Jennifer Doudna were able to hack this mechanism and the CRISPR-associated proteins known as Cas9 to edit DNA of other species. This breakthrough has had wide-reaching impacts in medicine, agriculture, and even climate change.

Living DNA’s parent company, DNA Worldwide, have been performing DNA testing for 20 years this year - long before Living DNA was set up. In 2013, in conjunction with with their laboratory partners Eurofins Forensic, they used a combination of forensic DNA profiling and genomic sequencing to prove the theory that even identical twins have differences in their genetic makeup.

Three years later in 2016, Living DNA was launched at New Scientist Live. Incorporating data from the PoBI project, we offered the most comprehensive recent ancestry breakdown of the British Isles available.

2020s

The last decade in particular has seen a boom in research into ancient DNA. With new methods we’ve been able to analyse older and older samples.

In 2022, researchers identified DNA in the soil in Greenland that was 2 million years old - the oldest DNA ever found. It belonged to willow and birch trees, as well as to mammals like the mastodon.

It's not just the soil - the artefacts our ancient ancestors have left behind are beginning to reveal their secrets as well. Just last year a paper was published in Nature that detailed how researchers have been able to extract the ancient DNA of a woman from the deer tooth pendant she had worn in life, 20,000 years ago.

The last 124 years has witnessed an extraordinary journey in the field of genetics, from the discoveries of the early 1900s to the emergence of CRISPR-Cas9 gene editing technology. Each decade has brought forth remarkable advancements that have reshaped our understanding of genetics and revolutionised biomedicine and biotechnology. As we stand on the brink of a new era in genetics, fueled by innovations such as personalised medicine, the possibilities for unlocking the secrets of life seem boundless.