Why are genetically modified sheep used to make a human protein to treat hereditary emphysema?

Genetically modified sheep are used to produce a human protein called alpha-1 antitrypsin, which is deficient in individuals with hereditary emphysema. By inserting the human gene responsible for this protein into the sheep's DNA, the animals can produce it in their milk. This method allows for large-scale production of the protein, which can be purified and administered to patients, helping to manage the disease and improve lung function. Utilizing sheep for this purpose is advantageous due to their ability to produce complex proteins similar to those found in humans.