Many centuries ago, dairy cows were genetically modified to produce larger amounts of milk during each milking time. This allowed dairy farmers to not only produce more milk each day, but in turn make their income larger in a shorter period of time.  However, this genetic change has proven to be a not so healthy change for those of us who drink milk.  Let me see if I can explain this in simple terms.  Milk is made up of 1) butterfat 2) whey 3) milk solids and 4) lactose (and other sugars).  The genetic change occurred in the 3rd category of milk solids.  There are many different proteins in the milk solids, of which one of these proteins is casein.  There are also many different caseins, the predominant one being the beta-casein.  This is where the genetic change from A2 to A1 was made.  Let's explore this area a little deeper. (Hang in there with me...I promise it will all make sense in a little bit.)  In the beta casein there is a chain of 229 amino acids, and at the #67 position of the chain is the amino acid proline.  All "old fashioned" breeds of cows have the amino acid proline.  The genetic change that happened in the proline amino acid, converted the proline to histidine. All A2 cows have the proline amino acid but A1 cows have the histidine amino acid.  Most milk you buy in the store is either A1 or A1/A2 and carry this modified amino acid.  Now, this is where it gets even scarier.  There is a side chain that comes off of the amino acid at position #67 that is a small protein peptide called beta-casomorpnin-7. (Yes...that big scientific word is WAY over my pay scale too!) Scientists call that big word BCM7 for short.  The scary part of BCM7 is that it is a powerful opiate.  Folks, opiates act like morphine and are known to cause undesirable effects in animals and humans.  As I mentioned earlier, A2 milk has proline, and proline binds strongly to the BCM7 and doesn't allow it into the milk which we consume. However, A1 milk has histidine and this is a weak amino acid which does not hold back BCM7 very well. Therefore, BCM7 shows up and develops in the GI tract of A1 cows AND the humans that drink this A1 milk. High quantities of this BCM7 have also showed up in the blood and urine of A1 cows. Here is a list of what BCM7 has been shown to affect:

BCM7 interferes with immune response, brain development and causes changes in brain function.

BCM7 provokes type 1 Diabetes in animal studies.

Populations that drink A1 milk have shown to have high levels of Auto-Immune Disease, Mellitus Disease, Heart Disease, Type 1 Diabetes, Schizophrenia, and Autism.

BCM7 has a pro-inflammatory effect on blood vessels.

BCM7 binds to epithelial cells in mucous membranes which stimulate the mucus in the nose. (This is a highfalutin way of saying it causes a constant runny, drippy nose.) 

All goats' milk, sheep's milk, any other non-genetically modified mammal's milk, even a mother's breast milk, is A2. This is why so many with "dairy issues" can drink goats' milk without having an upset stomach or harsh side effects. The question does remain...why does drinking A1 milk seem to affect some of us and not others?  More tests need to be done on the effects of A1 milk on humans, but some of the tests that have been done seem to point to the fact that those of us who have healthy GI tracts do not seem to be as affected by the A1 milk like some others may be.  However, we here at Drury Lane Farm have decided not to take any chances with our own family's health and will someday be producing some of the healthiest A2/A2 raw milk for ourselves in the future.  We truly can't wait!

If you would like to explore the subject of A2 milk even further, check out the book intitled "Devil in the Milk" by Keith Woodford.  Also, Dr. Thomas Cowan and Dr. Paul Dettloff have some great information online for you to read.  Let me know what you find out!