Scientists genetically modify lizards using CRISPR-Cas9 gene editing tool

Scientists from the University of Georgia have announced that they have become the first in the world to produce genetically modified reptiles. The team was able to produce four albino lizards using the CRISPR-CAS9 gene-editing tool. The CRISPR tool involves injecting gene-editing solutions into a newly fertilized egg or single-cell embryo.

This causes a mutation in the DNA that is reproduced in all subsequent cells. The team says that there were significant challenges with their breakthrough. One is that female reptiles store sperm in oviducts or long periods making it hard to pinpoint when fertilization happens.

The physiology of the reptile eggs, with pliable shells and no air space inside, makes it hard to manipulate embryos without damaging them. The reptile species the team worked with is called Anolis sagrei, commonly known as the brown anole. The team microinjected CRISPR proteins into multiple immature eggs in the lizard's ovaries that targeted the tyrosinase gene.

The team injected 146 oocytes from 21 lizards and waited for them to be fertilized naturally. Within a few weeks, the experiment had produced four lizards with indications the process was successful thanks to a quartet of albino lizards being produced.

This particular lizard species was chosen because it is spread throughout the islands of the Caribbean. All the lizards the team used for the study were collected in a wild area near Orlando, Florida. The team noted that the mutant lizards had displayed the manipulated tyrosinase in the genes inherited from the mother and father.

That shows that the CRISPR reagent remained active in the mother's oocyte. That indicates that the CRISPR reagent mutated the paternal genes post-fertilization.