Current Affairs

Issue

For the first time ever, doctors have managed to transplant heart of a genetically modified pig into a human body.

 

Background

The patient was ineligible for a conventional or artificial heart due to his medical conditions. Heart from a pig was a last shot.

 

Details

• Transplanting organs across different species is known as Xenotransplantation. The experiment first took place in 1984 when a baby received a baboon heart.

• The surgery was a success but the baby could not survive owing to the rejection by her body’s immune system.

• However, since many years, pig heart valves have been used to replace damaged human valves.

 

Need for genetically engineered pig

• The pig was genetically modified to make at least 10 genetic modifications that are needed to prevent rapid rejection of foreign organs by the human body.

• GalSafe pigs were used in the surgery. The pig had undergone genetic modification to remove gene that codes for Alpha-gal (a sugar molecule), which can elicit a devastating immune response in humans.

 

Modifications in pig

• Carbohydrate antigens were eliminated by removing of the CMAH and Beta-4-Gal genes of the pig.

• To maintain a human-sized organ, the growth hormone receptor gene was also removed.

• Two human anti-coagulant genes (EPCR and Thrombomodulin), and two human immune-modulating genes (CD47 and HO1) were inserted.

 

Significance

If Xenotransplantation becomes successful in the long run, it would provide humans alternative source for damaged body organs.