The world's first gene-edited lizards: Scientists reveal adorable pale pink hatchlings

Researchers at the University of Georgia say they’ve created the world’s first-ever genetically modified reptile — four of them to be exact — in a feat that could help further medical science.   

Utilizing the gene-editing tool CRISPR-cas9, scientists say they were, for the first time, able to fertilize the immature eggs, or oocytes, of 21 brown anoles, a type of tropical lizard. 

For scientists, this process was an accomplishment in and of itself — female brown anole can store sperm for long periods of time making it difficult to determine when an egg is fertilized and the eggs themselves are both small and fragile, making them difficult to manipulate.

The pink anole and the brown anole are separated by pigmentation through albinism. 

The target of researchers cutting and pasting, they said, was to deactivate the tyrosinase gene, which affects pigmentation. 

If the offspring produced by the female lizards were discolored, then the experiment had worked. 

Within a few weeks their efforts were realized when four atypically pink lizards displaying the telltale traits of albinism were produced. 

‘When I saw our first albino hatchling, it was truly awe-inspiring,’ said Dr. Ashley Rasys, who was first author on the study. 

‘I’m most excited about the possibility of expanding this approach into many other reptilian model systems, effectively opening the doorway for future functional studies.’

To the researchers surprise, the experiment also worked on the first try. 

Typically, to produce an albino offspring, both mother and father must carry the gene trait, but by altering immature eggs before they were fertilized the scientists were also able to affect the paternal genes, post-fertilization, as well. 

Just how that process takes place will be the subject of further study, they say.

In a first, researchers were able to alter the gene of reptiles to create the pink anole.

In addition to setting a precedent in genetically altering reptiles, researchers say the implications of their success could also aid the study of human medicine, particularly the eye.

The tyrosinase gene, in addition to affecting pigment, is also linked to the development of the human eye and is not present in mice, the most commonly studied proxy for human medicine. As a result, researchers say reptiles could help pioneer further research on the subject.

‘This work could have far-reaching impact not only for the study of reptile genetics but also for the advancement of genomic medicine and application in humans,” said David Lee, UGA vice president for research in a statement.

WHAT IS CRISPR-CAS9?

CRISPR-Cas9 is a tool for making precise edits in DNA, discovered in bacteria.

The acronym stands for ‘Clustered Regularly Inter-Spaced Palindromic Repeats’.

The technique involves a DNA cutting enzyme and a small tag which tells the enzyme where to cut.

The CRISPR/Cas9 technique uses tags which identify the location of the mutation, and an enzyme, which acts as tiny scissors, to cut DNA in a precise place, allowing small portions of a gene to be removed

By editing this tag, scientists are able to target the enzyme to specific regions of DNA and make precise cuts, wherever they like.

It has been used to ‘silence’ genes – effectively switching them off.

When cellular machinery repairs the DNA break, it removes a small snip of DNA.

In this way, researchers can precisely turn off specific genes in the genome.

The approach has been used previously to edit the HBB gene responsible for a condition called β-thalassaemia.