Milking cows? You heard it right! Learn more about “humanized milk” →

Breast milk is the safest and most nutritionally complete food for babies during their birth and early growth. It provides energy for the baby's growth and supports the development of important organs such as the baby's brain. However, today, some mothers breastfeed less frequently than before, either to maintain their figure or because of insufficient milk. Moreover, it is also very beneficial for people of other ages to consume human milk. Human milk can effectively regulate gastrointestinal flora, improve human immunity, and has a good preventive and therapeutic effect on diseases such as cancer.

Under such circumstances and demands, it is particularly important to develop a substitute for breast milk. Human milk is not enough, so cow's milk can make up for it. This problem will be solved by the "humanized" milk made by dairy cows.

Through genetic engineering technology, scientists have introduced protein coding genes that are nutritious to humans into dairy cows, allowing them to produce milk with nutritional value similar to human milk. Human milk contains extremely valuable proteins: human lactoferrin can improve human immunity, help the body resist allergies, resist radiation, and prevent various diseases; human α-lactalbumin contains rich amino acids that almost cover the needs of human growth and development, which can not only ensure people's sleep quality, but also promote brain development; human lysozyme is an important factor in resisting diseases, which can inhibit bacteria, resist infection, and enhance immunity.

However, the development process of "humanized milk" was not smooth sailing. The newly developed "humanized milk" contains many allergens. Only by removing them can "humanized milk" have value comparable to human milk. Researchers have found that by using zinc finger enzyme technology, the two β-lactoglobulin genes in milk can be deleted, and the "humanized milk" produced by cows will no longer contain the allergen β-lactoglobulin. In this way, scientists have successfully bred the world's first gene-edited cow. In addition, researchers have found another new method, using RNA interference technology to silence the β-lactoglobulin gene so that it cannot be expressed normally. Not only does it remove the allergen β-lactoglobulin, but it also makes another allergen-casein disappear. Double blow-a sure-fire move!

As a dairy product that needs to be provided to humans, especially infants and young children, how can scientists relax their safety inspections? The research department used mice to test and test "humanized milk". The results showed that "humanized milk" or recombinant human lactoferrin not only promoted the normal development of mice, but also alleviated some symptoms of mice infected with Salmonella and enhanced the autoimmunity of newborn mice. "Humanized milk" is very nutritious! "Humanized milk" is very healthy!

In 2011, relevant laboratories in my country successively established a basic group of new transgenic dairy cows with human lactoferrin gene, human lysozyme gene, human fucose gene, etc., and achieved efficient expression of recombinant human milk protein in the mammary gland of transgenic cows, with an average expression of more than 1 gram per liter. The research and development of "humanized milk" is a small step taken by scientists to solve the problem of insufficient breast milk. Perhaps in the future, genetically engineered milk that completely replaces breast milk will make a greater contribution to the nutrition of all mankind.