Meet Teodoro: Spain’s first genetically modified lamb

On July 5 1996, history was marked by a significant event for science enthusiasts with the birth of Dolly, the most renowned sheep of all time.

Dolly was successfully cloned by researchers at the Roslin Institute of the University of Edinburgh.

Now, in Madrid, a new scientific breakthrough has emerged with the birth of Teodoro, an extraordinary lamb. Born on an experimental farm belonging to the National Institute of Agricultural, Food Research and Technology (INIA-CSIC), Teodoro’s birth was not your typical lamb delivery.

It was achieved through genetic modification, a process that involved altering the lamb’s DNA to eliminate a specific protein.

Teodoro, the genetically modified lamb could help in understanding human fertilisation

This groundbreaking achievement is anticipated to provide insights into reproductive issues in farm animals. Surprisingly, researchers also believe that Teodoro could serve as a valuable model for understanding human fertilisation.

Pablo Bermejo-Alvarez, one of the researchers said, “Genetically modified animal models are essential to advance our understanding of any biological process, including those involved in reproduction. These animals contain targeted genetic modifications that eliminate or modify a specific gene and, therefore, allow us to know its function in a biological process unequivocally.”

CRISPR technology was used to create the genetically modified lamb, Teodoro

The revolutionary CRISPR technology has made these groundbreaking advancements in genetic engineering feasible. This gene-editing tool was co-discovered by French biochemist Emmanuelle Charpentier and American chemist Jennifer Doudna in 2012, and it has significantly transformed the field of genetic modification.

Prior to that targeted genetic modifications were primarily limited to mice due to the complexity and inefficiency of the techniques required for other mammals. However, the advent of CRISPR technology has opened up remarkable possibilities for precise genetic manipulation across various species.

Spain has genetically modified other animals but not in the same way as Teodoro

In fact, Spain is no stranger to using the CRISPR gene-editing technique to modify farm animal embryos, having already genetically modified rabbits and pigs several years ago.  However, up until now, it has not been necessary to generate genetically modified animals, and therefore, the embryos have been studied in vitro.

However, in order to obtain gametes from genetically modified animals to fully study the fertilisation mechanism, a decision was taken to transfer two genetically modified embryos, with one of the pregnancies reaching full term.

Welcome to the world, Teodoro; who knows, maybe one day you will be as famous as Dolly!