Craig Venter: 20 years of decoding the human genome – DW (English)

The decoding of the genome was a sensation, although the announcement by Craig Venter on April 6, 2000, was somewhat premature. It actually took another year before the Human Genome Project (HGP), which was in competition with Venter, published its peer-reviewed research results in the scientific journal Science and Nature on February 15, 2001.

Battle for first place

The decoding of the genome was a race for scientific fame between the HGP, which is government-funded by the US, and Venter with his private company Celera Genomics. The government researchers lagged somewhat behind Celera Genomics in their work. By April 2000, they had been able to decode only 54% of the human genome.

The genome is made up of the genetic storage material deoxyribonucleic acid (DNA). It contains all hereditary information of life.

Read more:Blood test detects more than 50 types of cancer

Craig Venter 1998 in the laboratory of his company Celera Genomics. Venter invented the shotgun sequencing method.

Going after the genetic material with a shotgun

Venter used a different sequencing method than the HGP researchers: namely, the so-called shotgun method that he developed. In this method, the individual DNA fragments are generated randomly. This is similar to shooting at the long chain with a shotgun and then looking at and reading out the fragments individually.

However, Venter also used HGP data to achieve his goal. And that was an ambitious one: The human genome consists of 3.2 billion base pairs the letters of life, so to speak. Finding them all was a mammoth task for him and the competing researchers. But the design of this genetic chain is actually quite simple.

It consists of a sequence of only four different building blocks: the DNA bases cytosine (C), guanine (G), adenine (A) and thymine (T). It is the sequence of these bases that determines our eye or hair color or whether we have any hereditary diseases.

Read more:Stone-Age 'chewing gum' reveals human DNA

Many doors leading nowhere

Only a few sections of the entire genome are the genes that contain important instructions for building blocks of life such as proteins. "According to current knowledge, however, a large proportion of DNA is an evolutionary remnant and has no function whatsoever. This makes it clear that although the door to the code of life has been opened, countless new doors are hidden behind it," writes chemist Friederike Fehr from the Max Planck Institute for Dynamics and Self-Organization in Gttingen.

Many genes that were discovered in the genome sequence had been unknown until then. "So the effects or tasks associated with them must also be researched. The sequence of letters alone is of limited help in this regard," Fehr writes.

Long road to medical applications

It was only with the completion of sequencing that the project of decoding the human genome could bear practical fruit. Although Venter published his own personal genome in the scientific journal PLoS Biology in 2007, this, too, was of rather symbolic importance. Gene sequencing in itself was only a first step toward a fundamental change in our medicine.

Scientists still had to research and assign the respective functions of the individual building blocks of the genome, i.e. find out which building block is responsible for what. They did this with the help of mice. Their genome is largely identical to that of humans and thus provided a basis for understanding the functions of human genes.

Experts believe that it could take dozens, if not hundreds, of years to really understand the human genome.

Read more:Who's the daddy: Does it really matter where your DNA comes from?

What do we get out of this?

The genomes of two people differ. These differences are the basis for the genetic predisposition to certain diseases.

Increasingly, genetic tests are being offered that enable experts to identify some of these predispositions and thus determine whether or not a person carries an increased risk of disease. A saliva sample is sufficient for this.

The most important thing in all these tests is to interpret the results correctly, for example, to determine if there is the disposition for Alzheimer's or diabetes.

With the help of genome research, it is now possible to identify various gene functions. This in turn helps doctors to treat certain diseases, including in children with an immune deficiency that is hereditary. Doctors can even implant new genes into these children to treat the disease.

Breast and ovarian cancer become apparent in the alterations of two genes (BRCA1 and BRCA2). A genetic risk for a tumor disease can be detected only in a few cases by genetic analysis.

There is still much to be done

The human genome consists of roughly22,500genes. Researchers around the world were astonished at this result as, believe it or not, a water flea has 30,907.

How complex a living being is, therefore, not dependent only on the number of genes. US President Bill Clinton said on April 6, 2000: "Now we are learning the language with which God created life." We now know that we still need a lot more vocabulary before we master that language.

This article has been edited and correctedsince it's first publication on 5 April 2020

Read more:Barley geneticists toast to future of better beer

In 1891, a Croatian born, Argentine criminologist, Juan Vucetich, started building up the first modern-style fingerprint archive. Since then, fingerprints have become one of the main forms of evidence used to convict criminals. Here, a police officer spreads dust on the lock of a burglarized apartment. Fingerprints become visible.

He uses an adhesive film to capture the fingerprint. Then he glues it to a piece of paper. In the past, comparing fingerprints was a painstaking affair. Officers had to compare fingerprints found at the scene of a crime, one-by-one, with those of possible suspects. These days computers do the job.

Taking fingerprints used to be a messy affair - with ink and dirty hands. These days scanners have replaced the inky mess. And the data can immediately be sent to a database and turned into biometrical data.

The computer identifies typical spots within the ridge patterns of the fingerprint. These include forks in the lines, spots and the location of the center of the print. Fingerprints are never the same between two people - not even with identical twins.

No chance! Here, officials use fingerprint scanners during an election in Nigeria. It's how they make sure the people voting are registered voters and that they only vote once.

This is an important question for officials who have to decide about the refugee or asylum status of applicants. In the European Union all migrants are supposed to have their fingerprints taken at the first point of entry - provided, of course, the local police officers are equipped with the scanners.

Many smartphones now come with fingerprint recognition software, such as the iPhone's Touch-ID. The owner of the phone unlocks it with his fingerprint. If someone else finds or steals the phone, they have no way of getting at any encrypted data within.

This is an Automatic Teller Machine (ATM) in the Scottish town of Dundee. Customers wanting to withdraw money need to show biometric proof of identity - in the form of a fingerprint. Not good news for pickpockets.

Since 2005, German passports, and many other passports, contain a digital fingerprint as part of the biometric information stored on a RFID (radio-frequency controlled ID) chip. Other information on the chip includes a biometric passport photo. The facial image is similar to fingerprints: no two images are alike.

Facial recognition software, which uses biometrics, is well advanced. It is possible to identify suspects within large crowds, with surveillance cameras. Also internet services and private computer owners are increasingly making use of facial recognition software to sort holiday pictures and tagging them to names.

Alec Jeffreys discovered DNA-fingerprinting almost accidentally in 1984 during research at the University of Leicester. He identified a specific pattern on DNA segments, which were different for every human. He created a picture, which looks like a barcode at the supermarket.

Germany's Federal Criminal Police Office (BKA) started storing such barcodes in a federal database in 1998. Investigators have since solved more than 18,000 crimes, using genetic fingerprints.

It's not just criminals who get identified. Many innocent people can be cleared of criminal charges through good identification. For some, technology has saved their lives. Kirk Bloodsworth spent almost nine years on death row. The US Innocence Project has proved the false incarceration of more than 100 people using DNA evidence.

The first big test for DNA-fingerprinting came with the mass murder of Srebrenica. Bodies, exhumed from mass graves, were systematically identified using DNA techniques. They were then reburied by their loved ones. Here, five year old Ema Hasanovic pays last respects to her uncle. More than 6,000 victims of the massacre - mostly men - were identified using DNA-fingerprinting.

You may be surprised, but there's biometric information in sounds and other digital data. Voice recognition software can, for instance, identify people making threatening phone calls - the human voice is also unique. And don't forget: we leave all kinds of digital traces on the internet, which hold clues to who we really are.

Author: Fabian Schmidt

Visit link:
Craig Venter: 20 years of decoding the human genome - DW (English)