Gene-Editing Technique May Take The Bite Out of Malaria

This year alone, malaria has claimed more than 400,000 lives and 91% of the deaths were in Sub-Saharan Africa. Researchers far away from the scourge at the University of California claim that they have created a new strain of mosquito that could make malaria a disease of the past. This was accomplished via a new gene-editing technique in which DNA is inserted into the germ line (line of descent) of the Anopheles mosquito, which refers to the  group of cells in a developing embryo from which reproductive cells develop.


Anopheles MosquitoAnopheles Mosquito

Gene manipulation

Scientists have been able to alter the genetic makeup of the deadly mosquitoes by using CRISPR, a gene-editing tool that is actually an ancient defense mechanism found in strep bacteria. The name is an acronym standing for Clustered Regularly Interspaced Short Palindromic Repeats.The magic of this technique is that it grants access to a cell's nucleus so that DNA can be removed and new or mutated  genes can be inserted.


CRISPR MehtodologyCRISPR Mehtodology

CRISPR is precise, efficient and flexible and has enabled scientists to produce a new strain of mosquitoes that carry genes, which block the transmission of malaria. This new breed of insects would reproduce in the wild with others of their species and produce progeny unable to spread the dreaded disease. CRISPR is easier to create and more efficient than other gene-engineering techniques and is more versatile as it can be used in any organism.

How does this gene-editing tool work?

Although its original function lay in the field of bacterial immunity, Cas9 is an enzyme that snips DNA, and CRISPR is a compilation of DNA sequences that instructs Cas9 exactly where to cut. Biologists feed the Cas9 the proper sequence, which is known as guide RNA, and the DNA sequence becomes an easily manipulated set of bits that can be cut and pasted at will.


CRISPR at WorkCRISPR at Work

In the words of Carl Zimmer, weekly columnist for The New York Times and prolific author of 12 scientific books:

"As the CRISPR region fill with virus DNA, it...represents the enemies the microbe has encountered. The microbe can then use this viral DNA to turn Cas enzymes (CRISPR-associated proteins) into precision-guided weapons. The microbe copies the genetic material in each spacer into an RNA molecule. Cas enzymes then take up one of the RNA molecules and cradle it. Together, the viral RNA and the Cas enzymes drift through the cell. If they encounter genetic material from a virus that matches the CRISPR RNA, the RNA latches on tightly. The Cas enzymes then chop the DNA in two,preventing the virus from replicating."

The current research was published in the early online edition of Proceedings of the National Academy of Sciences.

Future ramifications

When paired with other molecular biology tools, CRISPR could well become a force to reckon  with in ecology, disease prevention and conservation. Gene-altering techniques have potential beyond our wildest dreams and could mean altering the entire world and all of its ecosystems.

Still, despite the fact that CRISPR  requires more testing and field studies, the promise of a cure for malaria is a boon to all mankind.

Can you envision other ways genomic testing can benefit mankind?

Closing thoughts on scientific innovation:

If at first an idea is not absurd, then there is no hope for it. ~ Albert Einstein