What is life? It is a profound question and depending on who you ask, the answer will vary greatly. For geneticists, life can be found in the building blocks of all living organisms, DNA. The information that DNA carries is essentially the code needed to live and reproduce which is the aim of all organisms. So, can we then synthesize life if we have all the genetic information?
The question alone is enough to cause major debate. The thought of creating life in a lab seems to evoke images of the many horror movies we have seen regarding the topic. However, considering how many breakthroughs scientists have made in our lifetime, is it so hard to believe that creating artificial life is possible?
In this book summary readers will discover:
- The questions surrounding artificial life
- How studies of DNA helped in the quest to produce artificial life
- How Venter’s team produced the first synthetic genome
- The implications of this scientific achievement for the future
Key lesson one: The questions surrounding artificial life
The concept of artificial life is not a new one. In fact, it was back in 1828 that a German chemist, Friedrich Wöhler chemically synthesized urea, a component of urine, in a bid to prove that organic and inorganic materials were not all that different. This may seem like an inconsequential argument but given the time, the fact that a chemist artificially produced something that the human body made was shocking.
Since then, society seems to have split into two groups. Those with the belief that life is simply a bunch of cellular processes and chemical reactions and those who believe that life is dependant on a soul. The later idea was coined vitalism as it implies that some vital function animates life. Nowadays, it seems that the question is less about whether we can produce artificial life and more about whether we should. The implications of playing God has long plagued this debate. What would it mean if we could artificially create life? Would it be a great mistake? Would the lives that were created turn out to be monsters that we lose control over? And lastly, would mankind be punished by a higher power for getting too ambitious?
So many questions exist and beyond research, modern TV shows and movies weave the underlying fears of artificial life into their scripts. But just like DNA, science still evolves and perseveres. Now, biology, chemistry and computing have combined forces to create the branch of science known as genomics and genetic science with the hopes of unlocking life’s true meaning.
Key lesson two: How studies of DNA helped in the quest to produce artificial life
In the 1960s, there was a major discovery in the study of DNA. Scientists discovered something called restriction enzymes in bacteria. These proteins allowed scientists to essentially cut and paste segments of DNA together. Thus, scientists could henceforth slip genetic code into foreign DNA in a process known as gene splicing. This discovery spawned a whole new era of experiments and a decade later, scientists were already performing gene splice on more complex bacteria. Year by year, as new information was gained, further progress was made in gene-splicing experiments with scientists moving on to work with mammals such as mice. Gene splicing also enabled scientists to learn more about hereditary diseases such as cystic fibrosis.
DNA sequencing and research came to the fore in the 1990s when computer technology evolved to help in this field. Before the introduction of computers and DNA sequencing machines, sequencing a single gene took almost a year! With new technology, scientists were able to record genetic code sequentially into a computer. This meant that all this information could be stored digitally. At this time J. Craig Venter founded The Institute for Genomic Research. It became the world’s largest DNA-sequencing laboratory. It was here that Venter’s team became the first to sequence the DNA of a living organism.
Being able to store information digitally meant that the creation of a database of sequenced genomes was now possible. This made research and comparisons much easier. Scientists were now able to not only sequence a genome but compare it to others to identify differences and similarities. Research into developing a synthetic cell thus began with Venter’s team at the forefront of trying to determine the minimum number of cells that were needed to create life. They did this by comparing two different species groups with the aim of identifying common genes between them. They identified 480 common genes that could potentially be important to all living organisms. Then, scientists chemically synthesized an entire chromosome with these important genes. What they aim to do is to continue to narrow down the genes to focus on by eliminating genes from this chromosome and determining the effect.
Key lesson three: How Venter’s team produced the first synthetic genome
Venter’s team set out to produce a complete chromosome synthetically using computer code. They chose a virus called Phi X 174, which usually infects bacteria. The virus has 11 genes which made it easy to work with. Also, Phi X 174 had been used multiple times before in experiments and had already been genetically sequenced and its genome had already been copied. Their experiment entailed feeding the sequenced DNA of the virus into a computer. Next automated DNA synthesizers reproduced the code chemically. The team could then assemble the DNA like building blocks in the correct order. Once placed in order, enzymes were used to secure the DNA in their places. This synthetic DNA was then introduced into host bacteria. After a designated incubation period it was found that the synthesized DNA had in fact infected the bacteria. This proved that synthetic DNA, chemically built from computer code could function as the original virus.
The next logical step for Venter and his team was to consider repeating their experiment but using a living organism with a more complex genome. A virus after all is not considered living but more of protein covered genetic material instead. So the team considered a living organism with the smallest possible genome, Mycoplasma genitalium. This tiny bacterium gave the team no less than 582 970 base pairs of DNA to synthesize. Knowing that they had to maintain accuracy, the team broke down the genome into 101 segments of 5000 base pairs. These segments were referred to as cassettes.
The team synthesized each cassette individually and reassembled them later. They ensured that they would be able to reassemble the cassettes accurately by adding an overlapping sequence at the start and end of each cassette. Venter’s team also ensured the proprietary rights of their work by inserting watermarks in the code that was unique to their lab. After all this work with the genome, they then needed to find a stable environment to insert the code. They chose yeast cells with the new DNA. After careful inspection, it was discovered that they had successfully produced a synthetic bacterial genome for the first time. The next step would be to transplant this synthetic genome into a cell to create a synthetic organism.
The team started the process all over again using a different bacterium for the starting genomic material. They did this so they could use a bacterium that replicated faster than Mycoplasma genitalium so they could get their results faster. They used Mycoplasma mycoides and synthesized its genome as described previously. Next, came the difficult task of finding a suitable recipient cell to receive this DNA. Some cells have a defensive surface coat that destroys DNA on contact which they would need to get around. Eventually, the team discovered that polyethylene glycol had the ability to make the recipient cell’s membrane more permeable to the DNA. Their first attempt at transplanting the synthetic genome into a host cell did not work. The bacterium did not grow. They went back to identify the possible problem and found that they had left out a single letter in the base pair DNA sequencing. This simple deletion had thrown the entire experiment off. They corrected the sequence and tried again. It was a success! Venter’s team had successfully synthesized a living organism. This bacterium had a computer for a parent and had made genetic history.
The bacterium continued to replicate successfully with no outside interference meaning that it was solely controlled by the synthetic genome. As successful as this endeavour was, it was met with mixed responses. Many questioned if it were truly a synthetic organism as the recipient cell was natural and not synthesized. People were also sceptical as they believed a synthetic organism should be made from scratch. What was most evident though was the fear. What if this technology was exploited by bioterrorists? Whilst this is a valid fear, it must be remembered that this was a breakthrough in genetics. Of course, the use of this biotechnology would be regulated but the benefits of future research are limitless at this point.
Key lesson four: The implications of this scientific achievement for the future
The most exciting development from Venter’s team was the fact that DNA could be digitized before synthesizing. This means, in the future, there is potential for DNA to be transported to remote locations.
Consider the example of the first colonists on Mars. If they get sick and need antibiotics, they could isolate the bacteria infecting them and send its DNA sequence back to earth. Here, scientists can recreate the bacterium and make an antibiotic that could be sent back to Mars. All this would be done electronically, being referred to as biological teleportation.
Biological teleportation would enable research to occur between planets without having to worry about preserving samples for the trip back to earth. But even on earth, it could help in enabling samples to get to labs faster from remote locations which would be a huge benefit especially in times of disease outbreaks or when specific medications are needed.
The key takeaway from Life at The Speed of Light is:
Since the discovery of DNA, scientists have been fascinated and obsessed with solving its mysteries. Over the years, the field of genetics has grown and the evolution of technology also elevated research to a whole new level. More and more information is being unlocked and with this, more possibilities have been identified. Synthesizing a living organism may be a possibility, but it is just the first step of many. The future of this field of study is filled with possibilities that will be an advantage for the human race.
How can I implement the lessons learned in Life at The Speed of Light:
If you are interested in genetics, why not try getting your genome sequenced? There are many organizations that now offer this service. Not only will you get to learn about your origins, but you could also learn if you have any potentially harmful genes that may cause disease. Knowledge is power, and knowing about your genes can only be beneficial.
