University of California, Davis, have found that milk produced by transplanted genes in goats carry the gene for an antibacterial enzyme found in human breast milk.
Lysozyme is a protein found in the tears, saliva and milk of all mammals. It is found at high levels in human breast milk, however goat’s milk contains only 0.06 percent as much lysozyme as does human milk. Lysozyme inhibits the growth of bacteria by destroying the bacterial cell wall, causing the contents of the cell to leak out.
Because lysozyme limits the growth of bacteria that cause intestinal infections and diarrhea, and encourages the growth of beneficial intestinal bacteria, lysozyme is considered to be one of the main components of human milk that contribute to the health and well-being of breast-fed infants.
For more than a decade, UC Davis researchers have been looking for ways to enrich the milk of cows and goats with some of the beneficial compounds like lysozyme that are found in human breast milk. About eight years ago, they used gene-transfer technology to develop a line of transgenic dairy goats that carry the gene for human lysozyme and, consequently, produce human lysozyme in their milk.