Review article

Unravelling the “Secret of life”: The story of DNA Double Helix

discovery and a tribute to Dr. James Watson

S. Sreekumar

Former faculty, Department of Zoology, University College, Thiruvananthapuram, Kerala, India

Corresponding Author: S. Sreekumar, Email: ssreekumar53@gmail.com

Journal of Experimental Biology and Zoological Studies. 2(1): p 1-3, Jan-Jun 2026.

Received: 22/11/2025; Revised: 24/11/2025; Accepted: 05/12/2025; Published: 01/01/2026

__________________________________________________________________________________________

Abstract

Dr. James Watson, the co-discoverer of the double-helix structure of DNA and co-recipient of

the Nobel Prize in Physiology or Medicine with Francis Crick, passed away on 6 November

2025. This paper presents a historical account of the contributions made by earlier researchers

whose foundational work paved the way for Watson and Crick’s construction of the DNA

model and also highlights the individual contributions of Watson and Crick to the field of

molecular genetics. Furthermore, it serves as a tribute to Dr. James Watson, one of the most

brilliant biological researchers of the century.

Key words: Central dogma, double helix DNA, Francis Crick, James Watson, genetic code,

transcription, translation.

___________________________________________________________________________

Dr. James Dewey Watson

James Watson, the American molecular biologist who co-discovered the double-helix structure

of DNA (deoxyribonucleic acid), passed away at age 97 on November 6, 2025, in East

Northport, New York. Born in Chicago, Illinois, in 1928, he was the only son of James D.

Watson, a businessman, and Jean Mitchell. At the age of 15, he entered the University of

Chicago, completing his Zoology degree in just four years. Although initially drawn to

birdwatching and Ornithology, he soon realized that genes held the key to understanding life.

This led him to pursue a PhD in genetics under Salvador Luria at Indiana University,

Bloomington, where he studied viruses that infect bacteria. He earned his PhD in Zoology in

1950.[1] In 1951, at the age of 23, Watson joined the Cavendish Laboratory at the University of

Cambridge in England. Same year, he attended a symposium at Naples where he met Maurice

Wilkins of King’s College, London and saw for the first time the X-ray diffraction pattern of

crystalline DNA. The interaction with Wilkins sparked his interest in the chemistry of DNA.

Around the same time, he met Francis Crick, a physicist. Realizing their shared fascination

with uncovering the structure of DNA, Watson and Crick began collaborative research that

ultimately led to one of the most significant scientific discoveries of the 20th century.

The discovery of DNA structure

The key material Watson and Crick used to elucidate the structure of DNA was Photo 51, taken

by Rosalind Franklin.[2,3] Franklin was a postdoctoral fellow in Wilkins’ laboratory. It was an

X-ray diffraction image—a somewhat fuzzy pattern produced by X-rays scattering off DNA

molecules. This image was shared to Watson and Crick by Wilkins without the permission or

knowledge of Franklin. Photo 51 provided several crucial clues about DNA’s structure. It,

showed a pattern of black spots arranged in the shape of a cross. It can be reasonably assumed

that this black cross of reflections which dominated the image could arise only from a helical

structure. Another indication was that the molecule has two matching parts, running in opposite

directions.[3] The image also indicated that DNA had a repeating pattern of helical turns, and

revealed the dimensions corresponding to one helical turn, and the spacing between base pairs.

Watson and Crick spent considerable time building models and testing each idea against the

information obtained from this image. Finally, in 1953, Watson and Crick proposed a model

for the molecular structure of DNA. Their model described DNA as a double-helical polymer

composed of nucleotides, each consisting of a sugar–phosphate backbone that forms the two

strands of the helix.[4] The nucleotide bases project inwards, stacking on top of one another.

These bases pair specifically through hydrogen bonding, with adenine (A) always pairing with

thymine (T) and cytosine (C) with guanine (G). Of the four bases, A and G have a double-ring

structure and are known as purines; while the single-ring structures, T and C are called the

pyrimidines. The DNA thus resembles a twisted ladder with rungs formed of base pairs. The two

strands of the double helix run in opposite directions. This antiparallel arrangement ensures

proper base pairing, making the two strand perfect fits, and thus contributing to the stability of

DNA molecule. The discovery further highlighted how the molecular architecture of DNA is

intricately designed through evolution and exquisitely suited to its role as the hereditary material in

living organisms. The double-stranded structure and specific base-pairing enable DNA to replicate

by separating into two individual strands, each serving as a template for synthesizing a new

complementary strand. This elegant and highly accurate semi-conservative replication mechanism

explains how genetic information is faithfully copied within cells and reliably transmitted from one

generation to the next.

The discovery earned Watson and Crick the Nobel Prize in Physiology or Medicine in 1962.

Maurice Wilkins was also a co-recipient of the prize for this work. However, Rosalind Franklin

could not be honoured, as she had died of ovarian cancer at the age of 37 by that time. According

to the rules of the Nobel Committee, the prize will not be awarded posthumously, and it cannot

be shared by more than three persons. Many believe that injustice was meted out to Rosalind

Franklin twice: first, when her DNA X-ray photograph was shared with Watson and Crick

without her knowledge or permission, and later, by being denied the Nobel Prize. During the

same period, Linus Pauling, the American chemist who had described the structure of keratin, was

also attempting to determine the structure of DNA.[5] In fact, in early 1953, he proposed a three-helix

model for DNA. He might well have discovered the correct structure before Watson and Crick had

he had access to Franklin’s data.

Contributions of earlier researchers

Like many great scientific breakthroughs, Watson and Crick’s elucidation of the DNA structure was

the natural culmination of insights contributed by numerous researchers before them. DNA was

first identified in the late 1860s by the Swiss chemist Friedrich Miescher, who isolated a

substance he called “nuclein” from the nuclei of human white blood cells. [6,7] This substance

was later renamed “nucleic acid” and eventually “deoxyribonucleic acid” (DNA). Russian

biochemist Phoebus Levene made several foundational contributions to nucleic acid

chemistry.[8] He discovered ribose, the sugar in RNA, and later deoxyribose, the sugar in DNA.

He also correctly described the chemical composition of RNA and DNA molecules. In 1919,

Levene proposed that nucleic acids consist of a series of nucleotides, each composed of one of

the four nitrogenous bases, a sugar molecule, and a phosphate group. He was the first to identify

the correct order of the three major components of a nucleotide (phosphate–sugar–base).[9]

Chargaff’s rule

In 1944, Oswald Avery and co-workers provided compelling evidence that DNA is the

hereditary material.[8] Soon after, Austrian biochemist Erwin Chargaff contributed key insights

into DNA structure. He observed that DNA composition varies among species and discovered

that, within any given DNA sample, the amount of adenine (A) is approximately equal to

thymine (T) and the amount of guanine (G) is roughly equal to cytosine (C). In other words,

the total purines (A + G) usually equal the total pyrimidines (C + T). This relationship is now

known as ‘Chargaff’s rule’. Although Chargaff’s findings were essential to later breakthroughs,

he himself did not recognise that A pairs with T and C pairs with G in the DNA structure.[10]

Challenges and Breakthroughs

Cobb (2023) has provided a detailed account of the challenges faced by Watson and Crick and

how they successfully overcame them.[11] Interpreting the structure of DNA from X-ray

crystallography is challenging because the molecule does not have a fixed chemical structure;

the sequence of bases varies along its length. As a result, the diffraction images are not sharp

and often appear blurred. In fact, Watson and Crick obtained much of the essential data for their

DNA model from the Medical Research Council report prepared by Rosalind Franklin, rather

than from Photograph 51, as is commonly believed. DNA exists in two forms: the A-form and

the B-form. The drier A-form is slightly different in size from the wetter B-form. In the B-form,

each turn of the helix measures about 34 Å, whereas the A-form has only about 28 Å per turn,

giving the two forms slightly different shapes. As a physicist, Franklin was initially more

interested in the A-form because of its more crystalline structure. Wilkins, meanwhile,

preferred the B-form, as DNA inside cells exists in an aqueous environment. Franklin later

shifted her focus to the B-form as well. Detailed calculations indicated that if the bases were

separated by 3.4 Å, there would be ten bases per turn of the helix. It was also theoretically

possible to have twenty bases per turn if the structure involved a double repetition. For a long

time, Watson tried to cram twenty bases per turn into his models, reducing the spacing between

bases to 1.7 Å.

Based on information available from earlier studies, Watson and Crick began constructing

possible models using cardboard cutouts representing the bases and other nucleotide

components, arranging the pieces much like solving a puzzle. In November 1951, Watson

attended a seminar in which Franklin presented her X-ray diffraction data, suggesting that DNA

had a helical structure. Drawing on this information, Watson and Crick constructed their first

model of DNA and showed it to Franklin. The first model of DNA that Watson and Crick

produced was an unsuccessful three-helical structure, a triple helix. As Cobb notes, “It’s a

disaster. Franklin takes one look at it and laughs.” Franklin identified a critical flaw: their model

placed the phosphate–sugar backbone inside the helix. One of the corrections required was that

the hydrophilic phosphate–sugar backbones must lie on the outside of the molecule, where they

could interact with water, while the hydrophobic bases should be oriented towards the

interior.[5] Sir Lawrence Bragg, head of the Cavendish Laboratory, was embarrassed by Watson

and Crick’s blunder and temporarily halted their work.[5] However, a series of developments

soon prompted him to reconsider the decision. By that time, Franklin was preparing to leave

Wilkins’ lab for another position, and her departure created a vacancy in the DNA research

project. Bragg was also aware that Pauling was competing to solve the structure of DNA, and

given their longstanding rivalry, he allowed Watson and Crick to resume their investigations.

Crick’s advisor, Max Perutz, then permitted him to read a summary report of Franklin’s data.

Watson had also seen these results earlier, during Franklin’s 1951 lecture at King’s College,

but he lacked the expertise to interpret X-ray crystallography data. Crick, with his background

in X-ray diffraction, immediately recognized that Franklin’s findings supported a “twisted

ladder” configuration, with two nucleotide chains running in opposite directions. Their

progress was further hindered by an incorrect understanding of the atomic configuration of

thymine and guanine rings. This was because the reference books they relied on depicted the

bases in incorrect tautomeric forms. It was Jerry Donohue who provided the final cue and

pointed out that they were using the wrong base configurations and suggested the correct

forms.[11] His advice provided the crucial intuition they needed to revise their model. From

there, everything fell into place. On the advice of Donohue, Watson prepared new cutouts based

on accurate atomic configurations and placed the two strands of the molecule in the opposite

direction i.e., antiparallel to each other, a small crystallographic detail that Crick had long been

fixated on and which Watson had not fully understood. One Saturday morning, Watson turned

one of the cardboard base cutouts over and suddenly saw that A pairs with T, and C pairs with

G. This pairing created rungs of constant width between the two phosphate backbones in their

model. It also became clear that hydrogen bonds form between these base pairs, giving the

molecule a consistent and accurate shape. This adjustment proved decisive as the

complementary bases now fit together perfectly (A with T and C with G). The base-pairing

now made perfect sense as the model satisfied Chargaff’s rule.[5]

Significance of hydrogen bonds

Initially, Watson and Crick believed that hydrogen bonds played no role in the interactions

between the bases, but they later recognised their critical importance in the structure of DNA.

It is now known that the complementary base pairs in DNA are held together by hydrogen

bonds.[3] Adenine and thymine share two hydrogen bonds, while cytosine and guanine are

linked by three. Although individual hydrogen bonds are weak, the presence of a large number

of hydrogen bonds can provide considerable stability to the DNA molecule. Another advantage

of hydrogen bonding is that it allows the two DNA strands to separate readily during

replication. Moreover, hydrogen bonds contribute to the specificity of base pairing; they form

only between complementary bases. For example, hydrogen bonds can be formed between A

and T or between G and C, but not between A and G or between T and C. This pairing rule is

of considerable biological interest as it suggested a copying mechanism for DNA.[5,8] The

specificity in base pairing also ensures that genetic information is accurately copied during

DNA replication. Any errors in base pairing can lead to mutations. Hydrogen bonds also help

protect genetic information. In the double-helix structure, the base pairs—where the genetic

information is contained—are positioned internally. This arrangement shields the genetic

material from chemical reactions, thereby preserving the integrity of the genetic information.

Watson and Crick published their findings in a one-page paper, entitled "A Structure for

Deoxyribose Nucleic Acid," in the British journal Nature on April 25, 1953.[12] This paper

carried a schematic drawing of the DNA double helix prepared by Crick's wife, Odile. A coin

toss decided the order in which they were named as authors. Their article revolutionized the

study of biology and medicine and laid the foundation for modern molecular genetics. It

provided crucial insights into DNA replication and synthesis, the genetic code, the flow of

genetic information leading to protein synthesis, and the development of new technologies such

as DNA sequencing, recombinant DNA technology, Polymerase chain reaction (PCR), and

several other advancements in modern genetics.

Watson and Crick’s views on DNA replication were presented in a second article in Nature,

published on 30th May 1953.[13] In the years that followed, Crick further elaborated on the

implications of the double-helical model, proposing that the sequence of bases in DNA

constitutes codes, representing amino acids, through which genetic information is stored and

transmitted. Watson and Crick’s original article in Nature initially received limited attention.

Its full significance became widely appreciated only towards the end of the 1950s, when their

conclusions were experimentally confirmed by Matthew Meselson, Arthur Kornberg, and

others, through studies establishing the genetic code and its role in protein synthesis.[4]

Deciphering Genetic information

In 1961, Crick and his collaborators first demonstrated that a continuous sequence of three

bases on a DNA strand could code for an amino acid.[14] The first codon was cracked in 1961

by Marshall Nirenberg and J. Heinrich Matthaei, who performed an experiment using a cell-

free system from E. coli.[15] They found that an artificial RNA chain composed solely of uracil

bases (poly-U) produced a polypeptide made entirely of the amino acid phenylalanine,

demonstrating that the triplet UUU codes for phenylalanine. Subsequently, it was established

that a poly-adenine RNA sequence (AAAAA...) produced a lysine polypeptide, and a poly-

cytosine sequence (CCCCC...) yielded a proline polypeptide. This showed that the codons

AAA and CCC specify lysine and proline, respectively. Over the next few years, Nirenberg,

Philip Leder, and Har Gobind Khorana deciphered the full genetic code. [16,17] Crick and others

further contributed by demonstrating that codons are read in a non-overlapping, three-

nucleotide sequence.

Watson’s Professional life

Immediately after the elucidation of DNA’s structure, Watson joined the California Institute of

Technology, where he worked from 1953 to 1955 with Alexander Rich, for studying the

structure of RNA using X-ray diffraction.[1] He then spent another year (1955–56) at the

Cavendish Laboratory in England, again collaborating with Crick on the general principles of

virus construction. In 1956, Watson joined the faculty of Harvard University, where he

continued his research on the role of RNA in protein synthesis and gathered evidence for the

existence of messenger RNA (mRNA). Watson married Elizabeth Lewis in 1968.

In 1968, Watson became the Director of the Cold Spring Harbor Laboratory (CSHL) on Long

Island, New York, taking on roles in both scientific administration and research. In 1994, he

became its President and afterwards, its Chancellor. [1,5] Though sometimes described as

absentminded, he played a major role in transforming CSHL into a leading research and degree-

granting institution, with the establishment of the Watson School of Biological Sciences.

Watson, was at the helm of the Human Genome Project (HGP), when this was officially

launched in 1990. [1,4] The HGP was an international effort to sequence and map all of the genes

of Homo sapiens. He served as the first director at the U.S. National Centre for Human Genome

Research (later renamed the National Human Genome Research Institute, NHGRI) from 1988

to 1992. Watson’s explanation for why he accepted the offer to lead the Human Genome Project

was deeply emotional. One of his two sons, Rufus, was diagnosed with schizophrenia. In his

own words: “As he (Rufus) passed into adolescence, I feared that the origin of his diminished

life lay in his genes. It was this realisation that led me to help bring the Human Genome Project

into existence.”[5] As the project's director, Watson strongly advocated for open data sharing,

ensuring that DNA sequence information was made rapidly accessible to scientists globally.

He also advocated for strong ethical guidelines, including dedicating a portion of the budget to

studying ethical, legal, and social implications (ELSI) of genome research. He was

instrumental in establishing the project's international collaborative efforts and open nature. In

1992, Watson stepped down from the HGP because of alleged conflicts of interest involving

his investments in private biotechnology companies. He also could not agree with Dr

Bernadine Healy, who was then the new director. Watson opposed the attempts to patent gene

sequences, which he believed were not subject to ownership because they were ‘laws of

nature’.[5] Completed in 2003, the Human Genome Project produced the first full reference

sequence of the human genome—a milestone that has since transformed biology, medicine,

and biotechnology. Interestingly, in early 2007, Watson’s own genome was sequenced and

made publicly available on the Internet, being the second person to have a personal genome

sequenced in its entirety. Later, he accepted a position as an advisor to the Allen Institute for

Brain Science in Seattle, Washington, where the ultimate goal was to create an integrated gene

atlas of the brain and make it universally accessible online.[5]

Controversies

Watson’s later public image was marred by repeated controversy. In 1968, Watson published a

book titled The Double Helix, in which he recounted how “the secret of life” was discovered,

solving a fundamental scientific mystery: how genetic instructions are stored in living

organisms and passed from generation to generation.[18] In this book, he made degrading

comments about Rosalind Franklin, describing her as “hostile,” suggesting that she guarded

her work jealously and worked in isolation and even referring to her by the nickname “Rosy.”

However, Watson himself admitted in this book that he and Crick had obtained Franklin’s data

from her 1952 progress report to the Medical Research Council, without her knowledge. He

also noted that Franklin indirectly contributed to their work by suggesting certain corrections

to their initial DNA model. The book included unnecessary comments about her appearance

[5] that she “did not emphasise her feminine qualities” and questioned her intelligence and

speculated that she may have had Asperger’s syndrome.[19] Watson’s portrayal of Franklin

upset many, including Crick. He also felt that Watson misrepresented the partnership between

them and betrayed their friendship.

In his autobiography ‘Avoid Boring People’, Watson alienated further colleagues by calling

fellow academics “dinosaurs,” “deadbeats,” “fossils,” and “has-beens.”[20] A wider ethical and

social storm arose when he proposed that society might screen out people of lesser intelligence

through genetic testing. He also made provocative and often offensive remarks, most

infamously speculating about links between race and intelligence.[19] Watson stated that the

intelligence of Africans might differ genetically from that of other races. Similarly, he opined

that the skin pigment melanin boosts sex drive. His remarks were immediately condemned as

racist. The controversy ultimately prompted Watson to resign from his position at Cold Spring

Harbor Laboratory. In January 2019, the Cold Spring Harbor administration revoked the

honorary titles previously bestowed upon him, following the airing of the TV documentary

American Masters: Decoding Watson, in which Watson reiterated that his views on race and

intelligence had not changed. His long-criticized remarks about intelligence and race also

compelled London’s Science Museum to cancel a planned lecture, stating that his views “went

beyond the point of acceptable debate.” Furthermore, Watson sparked outrage for saying that

having more women around in science makes things “more fun for the men” and they are

“probably less effective”. [19] Another controversial statement was that women should have the

right to terminate a pregnancy if prenatal tests indicated the child would be homosexual. What

was most troubling about Watson’s offensive statements was how a Nobel laureate in science

could make such profoundly unscientific pronouncements. In 2014, Watson became the first

living Nobel laureate to auction off his Nobel Prize medal — in part to support future scientific

research. A Russian businessman purchased it for $4.8 million (about £3 million) and then

returned it to him.

Dr. Francis Harry Compton Crick

The story of unravelling the “secret of life” would be incomplete without acknowledging the

individual contribution of Francis Crick. Francis Crick was born on June 8, 1916, in

Northampton, England. He graduated with a BSc in Physics from University College, London

in 1937.[3,21] During the Second World War, he worked as a scientist at the Admiralty Research

Laboratory, focusing on the design of magnetic and acoustic mines. In 1947, Crick shifted his

interests from physics to biology and moved to Cambridge, supported by a studentship from

the Medical Research Council (MRC). In 1949, he joined the MRC unit headed by Max Perutz,

which later became the MRC Laboratory of Molecular Biology. During this period, he worked

on the X-ray crystallography of proteins and obtained his PhD in 1954. A crucial turning point

in Crick’s career was the beginning of his friendship in 1951 with the 23-year-old James

Watson. It was their collaboration that ultimately led to the Nobel Prize winning discovery of

the double-helix structure of DNA.

Contributions of Crick

In 1958, Crick proposed the fundamental framework known as the ‘Central dogma of

molecular biology’.[22] It states that genetic information flows in a single direction—from DNA

to RNA to protein, or in some cases from RNA directly to protein. This flow of information

involves three key processes:

 Replication (DNA to DNA): DNA makes an exact copy of itself.

 Transcription (DNA to RNA): The genetic information in a segment of DNA is

transcribed into messenger RNA (mRNA).

 Translation (RNA to Protein): Proteins are synthesized by linking specific amino acids

in an order dictated by the sequence of codons in mRNA.

A crucial part of Crick’s original formulation was that information cannot be transferred from

protein back to nucleic acid. Over time, several exceptions to the central dogma have been

recognized. For example, certain RNA viruses perform reverse transcription, synthesizing

DNA from an RNA template. Similarly, infectious proteins known as prions can replicate

without mediation by DNA or RNA. Crick also hypothesized that there must be an adaptor that

mediated between mRNA and amino acids which is now known to be the transfer RNA or

tRNA. This is referred to as the ‘Adaptor hypothesis’.[23] Meanwhile, Paul Zamecnik and

collaborators discovered the transfer RNA (tRNA);[24] but, due to its peculiar structure, Crick

was initially hesitant to accept that it was indeed the adaptor.[25]

The theories proposed by Crick persuaded researchers to work on the processes of transcription

and translation, leading to the elucidation of the genetic code. The elucidation of the genetic

code stands as one of the greatest scientific achievements of the 20th century.[22] In 1961,

Francis Crick, Sydney Brenner, Leslie Barnett, and Richard Watts-Tobin demonstrated that

three consecutive bases in DNA specify a single amino acid.[26] With this discovery, scientists

began cracking the ‘code of life.’ The first actual decoding of a “word” of the genetic code—

identifying the specific amino acid signalled by a given codon—was also reported in 1961 by

Marshall Nirenberg. Nirenberg and his colleagues, including Heinrich Matthaei and Philip

Leder, carried out a major part of the work in deciphering codons [15,16] that was completed by

Har Gobind Khorana.[17] Eventually, Brenner, Barnett, Eugene Katz, and Crick placed the final

piece of the decoding puzzle by demonstrating that UGA was the third stop codon.[27] The

codons are believed to be the same in all living organisms. To account for this universality,

Crick proposed the ‘Frozen accident hypothesis,’ suggesting that the genetic code evolved in

the last universal common ancestor and became fixed after it was established.[28]

Another important contribution from Crick was the ‘Wobble Hypothesis’.[4] Although there are

61 codons that specify amino acids, the number of tRNA molecules is much lower (around 40).

This is to say that most amino acids are encoded by more than one codon, indicating

redundancy or degeneracy of the genetic code. Crick’s Wobble Hypothesis (1966) explains the

basis of this degeneracy. [4,29] According to the hypothesis, the first two bases of a codon pair

strictly and precisely with the corresponding bases of the tRNA anticodon, whereas the pairing

at the third position is more flexible and can “wobble.” In other words, while the first two

codon–anticodon interactions must be complementary, the third pair can vary. This relaxed

base-pairing rule allows a single tRNA to recognize multiple codons, enabling efficient

translation despite the limited number of tRNAs.

Crick’s views on Consciousness and Evolution

In his later years, while working at the Salk Institute for Biological Studies in La Jolla, CA.

Crick turned his attention to neurobiology, focusing on how the brain works and the nature of

consciousness. [3, 22] He avoided active experimentation, believing that invasive studies of the

human brain were unethical. Instead, he preferred to synthesize existing research into

hypotheses about the molecular origins of consciousness. However, many found his ideas on

consciousness to be speculative and difficult to substantiate.

In 1973, Crick, along with Leslie Orgel advanced the ‘Theory of Directed Panspermia’,

proposing that life on Earth may have originated from microorganisms deliberately sent by an

extraterrestrial civilization aboard unmanned spacecraft. [22] He was so much fixated with this

idea that he published a book ‘Life Itself: Its Origin and Nature.’ However, the theory is

considered to be far outside mainstream science and has been widely regarded as a speculative

exaggeration lacking solid empirical support. Additionally, Crick voiced views on eugenics

that were troubling and not shared by the scientific community. These opinions are widely

considered problematic and do not reflect contemporary scientific or ethical standards.

As narrated by Tamura, Francis Crick continued to apply his formidable intellect throughout

his life.[22] He favoured collaborative work with exceptional partners: James Watson in

discovering the structure of DNA, Sydney Brenner in deciphering the genetic code, Leslie

Orgel in exploring the origins of life, and Christof Koch in investigating human consciousness.

He succeeded in coordinating research across diverse fields, performing like “a conductor of

the scientific orchestra”.[30] He was the author of several books that include “Of Molecules and

Men”, “Life Itself: Its Origin and Nature”, “What Mad Pursuit: A Personal View of Scientific

Discovery” and “The Astonishing Hypothesis: Scientific Search for the Soul.”[3]

Francis Crick died on July 28, 2004 at the age of 88.

Conclusion

Watson and Crick were relatively young and had limited research experience when they began

their collaboration. Watson had studied Zoology, while Crick’s background was in Physics;

together, their strengths complemented each other like the two strands of DNA. In scientific

research, intelligence, logical reasoning, and the ability to integrate information often matter

as much as, or even more than, extensive experimental work. Indeed, many classical scientific

discoveries are rooted in simple but powerful logical insights. The achievement of Watson and

Crick exemplifies this: they did not perform extensive experiments or rely on sophisticated

instruments and lengthy protocols. Instead, they synthesized existing data into a coherent and

groundbreaking model.

The nucleotide composition of DNA was identified in 1906. However, it took nearly fifty more

years to determine its three-dimensional structure, and another 10 years to fully appreciate its

biological significance with the deciphering of the genetic code in 1961. It is worth mentioning

that the Nobel Prize for this discovery was awarded just after that in 1962. It is widely believed

that Watson and Crick’s success in determining the correct structure of DNA was largely due

to their access to Franklin’s data and images. These undoubtedly helped them significantly, but

they were not the sole resources in their achievement. According to Cobb, nothing in Franklin’s

data directly “gave” Watson and Crick the structure of DNA. If the data alone had been

sufficient, Franklin herself would have determined the structure. The fact is that she too was

working with incorrect representations of the bases, relying on the same sources for

information and she did not have a Jerry Donohue to point out the correct base forms.[11] The

model of DNA proposed by Watson and Crick not only revealed its chemical configuration but

also delivered a package of concepts and ideas, on DNA replication, the genetic code,

transcription of genetic information, and its translation into proteins. The passing of James

Watson signifies the end of an era in molecular genetics, that established its foundation and

spurred decades of sustained, transformative research.

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