THE A1 vs A2 MILK STORY

Dr. J. RAJU

Ph.D. Scholar

Animal Nutrition

PVNR Telangana Veterinary University

WELCOME

THE A1 vs A2 MILK

STORY

• In September 2007 Keith

Woodford’s book. - NZ

• The story starts with the

remarkable epidemiological

evidence demonstrating the

strong association between

countries that have a high

intake of A1 milk and a high

incidence of both type 1

diabetes and heart disease.

What Is A2 Beta-Casein?

• About 39% of the protein in cows' milk is beta-casein

• Transports essential minerals and nutrients such as calcium and

phosphorous

• There are genetic variants of beta casein; A1 and A2, with minor variants

either classed as A1 or A2-like.

• When digested beta casein can produce a range fragments with well

characterized biological activity

Composition of solids in

milk

Composition of milk casein

Figure from: MILK PROTEIN POLYMORPHISM: DETECTION AND DIFFUSION OF THE GENETIC VARIANTS IN BOS GENUS, Annali della Facoltàdi Medicina Veterinaria, Vol. XIX, 1999. Università degli Studi di Parma ]

A2 is the Original type of Bovine Beta Casein

• A2 is recognised as being the original or ancestor beta casein

gene in modern cattle.

• Originally all domesticated cows produced milk containing only

the A2 type of beta casein, owing to natural genetic mutation, a

variant of the A2 protein appeared.

• Termed A1, it differs very slightly in composition from the

original A2 protein

7

Ser

Difference in Structure and Digestion of A2 vs. A1

a2 beta caseinprotein chain (209aa)

a1 beta caseinprotein chain (209aa)

Val Pro Phe Pro Gly Pro Ile

Tyr

Pro PhePro

Gly Pro Ile

Amino Acid position 67

Amino Acid position 67

Asn Ser Leu Pro

TyrPro

PhePro Gly

ProIle

Pro Asn

Val Pro Phe Pro Gly Pro Ile Pro Leu Pro

digestion

digestion

A2 release BCM - 9

A1 releases BCM - 7

Reported as strong exorphin

AsnTyr

Tyr His

Adapted from: Gobbetti M, Stepaniak L, De Angelis M, Corsetti A, Di Cagno R. Latent bioactive peptides in milk proteins: proteolytic activation and significance in dairy processing. Crit Rev Food Sci Nutr. 2002;42(3):223-39. & Jinsmaa, Y & Yoshikawa, M. 1999. Enzymatic release of neocasomorphin and beta-casomorphin from bovine beta-casein. Peptides V20(8), pp 957-962.

9

>100,000 yrs ago

taurus and indicus species evolve from bos genus

European bos taurus e.g. Holstein, Jersey, Guernsey (A1 and A2 in all breeds)

African bos taurus eg. Kuri (A2)

African bos indicus e.g. Africander (A2)

Asian bos indicuseg. Brahman (A2)

bos taurus

bos indicus

~5,000 yrs ago

Variant A1 evolves through natural mutation from beta casein A2 in bos taurus

Ancient bos (Auroch )

Breed Evolution and Beta Casein type

Figure adapted from information reported in:1. Advanced Dairy Chemistry: Volume 1 - Proteins, Second Edition, edited by P.F. Fox and P. L. H. McSweeney pp 424 & 4302. MILK PROTEIN POLYMORPHISM: DETECTION AND DIFFUSION OF THE GENETIC VARIANTS IN BOS GENUS, Annali della Facoltà di Medicina Veterinaria, Vol. XIX, 1999. Università degli Studi di Parma3. Daniel G. Bradley, Ronan T. Loftus, Patrick Cunningham, David E. MacHugh (1998) ‘Genetics and domestic cattle Origins’ Evolutionary Anthropology V6;3 pp79-86

BCM7

The effects on human health of this tiny

protein fragment called beta-

casomorphin-7 (BCM7) which is a

powerful opioid or narcotic as well as

being an oxidant

Problems with A1..?

Increased incidence of:

• Type 1 diabetes

• Leaky gut syndrome

• Heart diseases

• Others

13

Recent research on BCM-7

• Previously studies established that:

• Digestion of A1 but not A2 produces protein fragment beta

casomorphin-7 (BCM-7)

• BCM-7 binds opiate receptors and has the potential to interact with

a range of tissues

• Precursor protein A1 is linked to a range of negative health

outcomes

• Recent clinical trials report BCM-7 production to physiologically relevant

levels in the gut of healthy adult humans. (Boutrou et al, 2013)

• A correlation between BCM-7 levels with delayed psychomotor function

in formula fed human infants has been reported (Kost et al, 2009)

• Serum BCM-7 has also been linked to the compromise of breathing in

infants fed A1 containing formula (Wasilewska et al, 2011) .

• A mechanism by which BCM-7 leads to oxidative stress and cell

dysfunction has subsequently been demonstrated (Trivedi et al, 2012).

14

Research Highlights

Though clinical trials are required to confirm links with health

conditions, the following is established:

• BCM-7 has the potential to bind opioid receptors expressed in

cells throughout the body, including digestive, immune and

neurological

• BCM-7 has been observed to be produced, absorbed and

circulated in some humans, particularly infants

• Emerging research links BCM-7 to adverse effects on infant

development and health, and intolerance type reactions in

adults

• Recently a mechanism by which BCM-7 triggers oxidative

stress in cells leading to changes in short and long term

function was demonstrated

Detailed scientific summaries and study references contained on www.betacasein.org and www.betacasein.net

Devil in the Milk….?

Jersey cow produces A1 Milk

Angel in the Milk…?

Indian cow produces A2 milkExport potential …!!!

Thank you…