Molecular Basis Of Inheritance
In case you need a recap, here are some good videos on the important topics:
Table of Contents
What have we done with knowledge of genetic codes?
Edit your own DNA with the CRISPR-CAS9 technology
CRISPR, pronounced ‘crisper’, stands for Clustered Regularly Interspaced Short Palindromic Repeat. The name refers to the way short, repeated DNA sequences in the genomes of bacteria and other microorganisms are organised.
For years “genetic engineering” seemed possible only in the movies but with the rise of a cheap and precise technique for DNA editing, CRISPR-CAS9, such control over biology is now in our grasp. The technique allows geneticists to modify, delete or add genes with unprecedented accuracy, effectiveness, and flexibility – but how does it work and why is it so controversial?
CRISPR is a spinoff for these organisms’ defence mechanisms. Bacteria defend themselves from viral attacks by stealing strips of the invading virus’ DNA, which they splice in their own using an enzyme called Cas. These newly-formed sequences are known as CRISPR. The bacteria make RNA copies of these sequences, which help recognise virus DNA and prevent future invasions.
But is it all that supercool? Let’s bust some myths.
Why have one when you can have Dolly? Clones are the answer!
Cloning is the process of making a genetically identical organism through nonsexual means. It has been used for many years to produce plants (even growing a plant from a cutting is a type of cloning).
Animal cloning has been the subject of scientific experiments for years, but garnered little attention until the birth of the first cloned mammal in 1996, a sheep named Dolly.
The unfertilized eggs of some animals (small invertebrates, worms, some species of fish, lizards and frogs) can develop into full-grown adults under certain environmental conditions — usually a chemical stimulus of some kind. This process is called parthenogenesis, and the offspring are clones of the females that laid the eggs.
Another example of natural cloning is identical twins. Although they are genetically different from their parents, identical twins are naturally occurring clones of each other.
Why do people actually need clones?
The main motive behind the cloning is to mass harvest organisms with selected qualities for instance, E.coli have been engineered to produce human insulin.
If you had to rely on sexual reproduction (breeding) alone to mass produce these animals, then you would run the risk of breeding out the desired traits because sexual reproduction reshuffles the genetic deck of cards.
Other reasons for cloning might include repopulating endangered or even extinct species. Whatever the reasons, the new cloning technologies have sparked many ethical debates among scientists, politicians and the general public. Several governments have considered or enacted legislation to slow down, limit or ban cloning experiments outright. It is clear that cloning will be a part of our lives in the future, but the course of this technology has yet to be determined.
Are We Close To Removing Extinction?