Answer:
When more things were discovered about DNA, different methods were devised to manipulate it. The mutations in the genes were isolated and mixed with the intention of obtaining a beneficial mutation. For example, a tomato that better supports frost or a wheat resistant to various diseases. Many of the foods we eat have been improved as well.
Mutagenesis goes a step further by treating DNA with chemical compounds to force the appearance of a mutation, and hopefully, it is beneficial. But these first methods were almost entirely based on luck. No one knew if a mutation was going to appear or not, and what effects it would have.
What is CRISPR, the genetic cut and paste that cures diseases
The next big step took place with transgenics, which consist of introducing genes from one organism into another. Here, very good results have been obtained, giving rise to the transgenic foods that we all know. More resistant to diseases or weather, larger or more fertile. But it is not yet known what effects the use of genes external to the organism has in the long term, and there is an ethical component related to genetic manipulation applied to animals, and even people.
CRISPR, the scientific discovery of the year
Genetic manipulation in humans aims to eliminate serious hereditary diseases. It is known that there are fatal diseases that have a significant genetic burden, from certain types of cancer to malformations, sterility or hemophilia, and people who inherit the genes have a high chance of suffering them. The latest medical advances in molecular genetics allow to identify DNA mutations that cause diseases or malformations, and eliminate them during pregnancy so that they do not manifest themselves.
This type of genetic manipulation is quite limited. It cannot be applied to any DNA chain even in all cases. Until now. This is where CRISPR comes in, a DNA manipulation technique that allows you to apply a cut and paste to the DNA. Literally, a DNA fragment can be cut and replaced with another fragment of the same individual, or repaired.
