“WORLD’S FIRST LIVING ORGANISM WITH FULLY REDESIGNED DNA MADE”

The world’s first living organism with fully redesigned DNA has been made by scientists of the Medical Research Council’s Laboratory of Molecular Biology in Cambridge. The organism comprises of a fully synthetic and radically altered DNA code. Researchers have taken about a two-year effort to read and redesigned the DNA of the bacterium Escherichia coli i.e E coli.  The research proved that life can exist with a restricted genetic code and is helpful to make drugs for viral resistance. This strain of bacteria is normally found in soil and the human gut. (1)

Gene editing for rewriting the code of life 

The artificial genome holds 4m base pairs. The units are spelled out as G, A, T, and C. It runs to 970 pages on printing in full on A4 sheets. This is the largest genome that scientists have ever built. Jason Chin, an expert in synthetic biology led the project. The DNA holds the instructions for functioning. It also encodes the right protein when cell demands to grow.  The letters coded as DNA in trios are called codons, For example, TCG and TCA. All the life right from the jellyfish to humans uses nearly 64 codons. Totally 61 codons make 20 natural amino acids to build any strong protein structure. Three more codons indicate the signal when protein synthesis is complete. (2) 

The work of the scientist on Gene Editing 

The team of researches redesigned the E coli genome by removing some of its superfluous codons. The scientists have gone through the bug’s DNA. TCG was rewritten as AGC which shares the same job. They replaced two more codons in a similar way. The scientists had removed the occurrence of the three codons from the bug’s genome after editing it for more than 18,000. The natural genome of E coli was replaced by chemically synthesized redesigned genetic code. The new bug was named as Syn61 which is a little longer than normal, and grows more slowly but survives nonetheless. (3)

By this method it is possible to make the invading viruses to struggle and to spread inside them, making them in effect virus-resistant. E coli is already used to make insulin for diabetes and other medical compounds for cancer, multiple sclerosis, heart attacks, and eye disease. The entire production can be easily spoiled when bacterial cultures are contaminated with viruses or other microbes. In future work, the genetic code could be repurposed to make cells churn out designer enzymes, proteins, and drugs. The biggest revolution in gene editing was made by Crispr-Cas9. This was reported by US scientists in 2010. (4)

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