What are Jumping genes? How is it an alternative to CRISPR-Cas9?
Introduction: (up to 30 words) Explain the concept of genome/DNA editing
Body: (up to 100 words) Explain and write about CRISPR-Cas9 technology, Jumping Genes and how Jumping genes could be a safer alternative
Conclusion: (up to 30 words) Mention the advantages, use and applications of such processes
Genome editing, or genome engineering, or gene editing, is a type of genetic engineering in which DNA is inserted, deleted, modified or replaced in the genome of a living organism.
Scientists have recently discovered a technique using “jumping genes” for genetic editing. It could offer a seamless, safer alternative to CRISPR-Cas9 process.
The technique could allow edited genes to be more precisely inserted into genomes, possibly addressing concerns with current CRISPR systems that can lead to off-target editing and random deletions or even cancer.
CRISPR tools currently use enzymes like Cas9 and Cas13 to cut and delete a portion of the genetic code, counting on the cell to use its repair function to glue the cut strands back together.
The process is not always effective, sometimes the repairs are incomplete or incorrect, and the damage response prompted by the cutting can have negative side effects.
Transposons or Jumping Genes:
Jumping genes are also known as transposons, it randomly jumps from one site to the other, inserting genetic information as they go, using enzymes called transposases.
A transposable element (TE, transposon, or jumping gene) is a DNA sequence that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genetic identity and genome size. Transposition often results in duplication of the same genetic material.
It can effectively slide into the DNA without cuts.
The jumping gene possesses all the necessary chemical properties to directly insert, or integrate without a DNA double-strand break.
Jumping gene could effectively be programmed with a guide, and it can insert itself with incredible precision into user-defined sites in the genome.
Researchers sequenced the edited genome and found that the insertion was precisely done, with no extra copies created elsewhere, a problem that can occur with gene editing that uses CRISPR.
TEs are mutagens and their movements are often the causes of genetic disease. They can damage the genome of their host cell in different ways:
A transposon or a retrotransposon that inserts itself into a functional gene will most likely disable that gene;
After a dna transposon leaves a gene, the resulting gap will probably not be repaired correctly;
Multiple copies of the same sequence, such as alu sequences, can hinder precise chromosomal pairing during mitosis and meiosis, resulting in unequal crossovers, one of the main reasons for chromosome duplication.