If your body is a movie, then DNA is its director; if your body is a book, then DNA is its writer. What we do, feel and think comes from DNA. So, imagine if we could interpret the coding of DNA. That would mean we could read the manuscript of our own lives! But guess what? It is far easier said than done.
The human body is composed of around 37.2 trillion cells. In each cell, there is DNA present in the nucleus. Each DNA strand is made up of nucleotides and contains different codes like AGCT. These codes are composed of 3 billion chemicals in different combinations. On the brighter side, 99.9 % of every human DNA is the same. It is that 0.1% that makes us all different.
So how exactly did we read all those codes? It was the work of many individuals from all around the world. This is the story of Human Genome Project.
Human Genome Project: A Study of Our Own Instruction Book
It all began in 1984, when Alec Jeffery, a British geneticist, made a momentous discovery. He was studying the inheritance of diseases through families when he stumbled upon something peculiar. He noticed that one particular region in DNA was different in every individual. It was a region that repeated itself over and over (the region that is now known as Short Tandem Repeat or STR). This excited Jeffery beyond limits as he realized that with this discovery every human being could be identified from the other. He quickly started experimenting on every single thing containing DNA. Ultimately, he was able to match every DNA sample to its rightful owner. Jeffery named this technique as ‘DNA fingerprinting’.
Soon its application gained overwhelming fame. Hundreds of paternity disputes were solved using this technique and then in 1988, the first rapist was convicted using DNA fingerprinting.
Then came Fred Sanger on the scene. He took the responsibility of reading the codes on gene. Sanger knew better than to experiment on human genes right away because of its complexity. Instead, he blew open a virus’ DNA, using high frequency waves, took a piece of it and began reading it.
DNA is made up of nucleotides and nucleotides are made up of four different chemicals: Adenine, Cytosine, Guanine and Thymine. These chemicals are denoted by their first alphabets like A for Adenine or G for Guanine. Sanger’s trick was to use 4 different chemicals which he placed on the ends of the DNA fragments. One of the chemicals reacted with all the G’s present on the strand while another one reacted with all the A’s and same thing happened with C’s and T’s. Now Sanger could identify all the letters present on the code. It took Sanger 4 years to read the virus’ 5000 letter code. Hence Sanger became the first person ever to read a living organism’s instruction book.
But deciphering the human genome was not a single person’s job. It was believed that the human genome contained 3 billion nucleotides. Obviously, it was a much bigger project and needed many hands.
This interested the legendary molecular biologist and geneticist, James Watson. In 1986, he invited 400 scientists to his lab to discuss the problem. It was concluded that the task was possible but needed to be treated as an industrial project. It was estimated that a single person could decipher around 100,000 letters in a single year. But the cost of the project could reach up to 3 billion dollars. The problem now was that who would spend billions on this project? James Watson, one of the discoverers of DNA structure, was the only person who could convince the United States Congress to hand over that much money.
He put forth the idea that diseases like cancer and diabetes could be cured if one could read the genetic codes.
Watson was already an influence over the politicians as he had made a name by working out the DNA’s model and the Congress could not let go of such an important opportunity. The Human Genome Project was, consequently, authorized in 1990 by the United States Congress. Hundred anonymous people gave their blood and semen samples and the sequencing began.
In 1992, James Watson was succeeded by one of the greatest genetic disease researchers, Francis Collins. With the completion date set for 2005, he quickly realized that in order to achieve their goal they would have to divide the work. So, the chunks of DNA were separated and sent to 16 different universities including Beijing and Harvard. As the work was being done at various places and by various hands, it was necessary to have bookmarks to place together all the pieces. Short Tandem Repeats were bigger pieces with repeated letters so it was easier to piece together broken Short Tandem Repeats. Alec Jeffery might not have been directly involved with the Genome Project but his research was one of the major breakthroughs that paved way for it.
Eight years had passed since the authorization by Congress but only a third of the genome had been deciphered. This sluggish speed frustrated a scientist named Craig Venter. He proposed that instead of sequencing, it was better to blow up the whole genome in a shotgun fashion, then collect the pieces and feed those to supercomputers which would piece them together just like a jigsaw puzzle. He found a lab in Silicon Valley equipped with supercomputers and claimed that the Genome Project could be completed in 3 years with far less investment.
But his ideas were met with skepticism.
The Publicly Funded Team, led by Collins, did not believe that the whole project could be completed in such a hurry. But when in 1998, Craig Venter came forward with a privately funded lab named Celera and a promise to complete the project in next three years, the publicly funded team panicked. Craig’s lab was equipped with robotic sequencers working with light speed. The publicly funded team faced two major problems, one that the Congress could withdraw the whole funding and the other that Craig’s team intended to sell this information to drug companies. Thus, the race began.
James Watson approached the Congress for more funding and persuaded them to hand over 80 million dollars. With this money they approached Tony White, the owner of the company which produced robotic sequencers and the privately funded lab (Celera) that Venter had suggested. Technically the people in the government were his rivals but White agreed to sell a single robotic sequencer for 300,000 dollars. The government bought 300 pieces. With these machines at hand, the public team started making quick progress. Soon they started uploading the information about important genes related to diseases like diabetes and cancer on their website freely, for everyone to access. With this move, all the plans of Celera to sell such information were jeopardized.
Then Celera announced that they were about to file a patent for owning the whole project. This announcement sent an excited wave among the public. Everyone was curious to know what Celera would become. Soon their shares reached as high as 500 dollars a piece. That is when the President Bill Clinton decided to step in. He made it clear that Human Genome Project belonged to every single human being equally so there was no chance that Celera could have it to themselves. Hence the market crashed.
But Clinton was not satisfied. He was frustrated by the childish behaviour exhibited by Celera as well as the Publicly Funded Team. He invited them both at the White House and gave them a deadline of 6 weeks to release the first draft of Human Genome Project. He also made it clear that they would announce the result at exactly the same time so that there could be no room for dispute.
But it was not so easy to assemble the sequenced pieces from 16 universities together. Neither was it easy for Celera to piece together the blown-up pieces, especially within six weeks. Both the parties decided to take help from computer programmers.
Francis Collins found Jim Kent, a computer programmer, to do the job for him whilst Celera pushed the task towards their genome sequencer, Gene Meyer. Despite having the largest civilian super computer, Meyer did not find the task simple as the data was scattered and there was no map available in Celera. Eventually he had to download it from the website of the Publicly Funded Team- his rivals.
In a way, both the parties could not complete the task without each other; the public team had to buy supercomputers while Celera had to download the map provided by their rivals. Then on the 26th of June 2000, Craig Venter and Francis Collins announced the first draft of Human Genome Project together, along with President Bill Clinton. The differences between both the parties were resolved.
Fortunately, the winner was the human race.
It is due to this momentous project that we are now able to map out the important genes related to serious diseases such as cancer, schizophrenia and diabetes. But guess what? The battle is not over. We have been able to read the letters of our own instruction book but do we comprehend it?