Genomes are a point of great interest to us. After all, it is the genetic material of any organism that differentiates it from the others. My genes are what make me different from you. Was there a method to make my genes identical to yours, we would theoretically be twins in all aspects. Needless to say, the field has generated huge amounts of interest from scientists. Now, researchers have hit upon a way to dramatically reduce the cost of building and sequencing genomes.
At its most basic, a genome can be defined as the genetic material of an organism. It consists of DNA (or RNA) and has the genes (as well as the non-coding DNA and the genetic material of the mitochondria and chloroplasts. In short, this is exactly where our story is written and all of our traits are pre-defined.
I would like to call upon an excellent analogy from the Wikipedia to establish the scale of the human Genome:
An analogy to the human genome stored on DNA is that of instructions stored in a book:
- The book (genome) would contain 23 chapters (chromosomes
- Each chapter contains 48 to 250 million letters (A,C,G,T) without spaces;
- Hence, the book contains over 3.2 billion letters total;
- The book fits into a cell nucleus the size of a pinpoint;
- At least one copy of the book (all 23 chapters) is contained in most cells of our body. The only exception in humans is found in mature red blood cells which become enucleated during development and therefore lack a genome.
Obviously, the sheer scale makes genome sequencing extremely hard. Earlier researchers were deploying computers to stick small pieces of genetic code together. This served the purpose but the cost ran into hundreds of thousands of dollars as soon as you tried to be more specific — and say, tried to do sequencing for a particular person. However, scientists have now developed a new technique that uses folding maps to come up with a full sequence.
In this method, only short reads of the DNA are required. As you don’t need to slog your way through all the code stored in the genetic material, the subsequent cost of sequencing is significantly lower.
Now how would this be helpful? Well, to start with, scientists will be able to sequence the genomes of individual humans and discover why certain people fall prey to certain disease while others don’t. Think about it. There are humans amongst us that are highly resistant to certain disease. By studying their gene sequence, scientists could well determine what keeps them resistant and use it to come up with external cures and vaccines. That is not all though, scientists would also be able to catalog the gene sequencing of more and more species and this could well lead to discoveries on its own.
