Genetic Engineering Overview:
Early Stages (1970s-1990s):
Identification of Genes: Scientists began by identifying specific genes responsible for certain traits in organisms.
Isolation of Genes: Once identified, these genes were isolated from the DNA of an organism. Enzymes were used to cut out the desired gene from the larger DNA sequence.
Insertion into a Vector: The isolated gene was then inserted into a vector, often a plasmid (small, circular DNA), which acts as a carrier to introduce the gene into a host organism.
Host Organism Transformation: The modified vector, carrying the desired gene, was introduced into a host organism, such as bacteria. The host organism then replicated, producing copies of the gene.
Expression of Genes: The inserted gene in the host organism was expressed, meaning it began to produce the desired trait or protein.
Advancements in the 21st Century:
Precision and CRISPR-Cas9 Technology: In recent years, a revolutionary tool called CRISPR-Cas9 has been developed. This technology allows for precise editing of specific genes within an organism's DNA.
Targeted Gene Editing: Unlike earlier methods, CRISPR-Cas9 enables scientists to target and edit specific genes with unprecedented accuracy, reducing the risk of unintended changes.
Multiple Gene Editing: CRISPR-Cas9 allows the editing of multiple genes simultaneously, offering the potential for more complex modifications.
Applications Beyond Bacteria: While early genetic engineering primarily focused on bacteria, the advancements in CRISPR-Cas9 have expanded applications to various organisms, including plants and animals.
Therapeutic Gene Editing: In medicine, genetic engineering is being explored for therapeutic purposes, such as correcting genetic disorders by editing the patient's own cells.