[Tucson Jim]

Could also be the blood type of individuals who are allergic to milk.

http://www.webmd.com/diet/eat-right-for-your-type

I can take “Lactose Free” regular milk. Otherwise, cow’s milk gives me hemmoriods. A real pain....

[muawiyah]

The problem here is that East Asians, West Asians, South Asians, North Americans, South Americans, Africans and Europeans ALL developed agriculture in roughly the same time frames ~ there have been a wide variety of genetic changes that seem to be associated with peculiarities in some regions ~ e.g. genes for digesting rice easier, genes for digesting dairy products, genes for digesting seals and other high iron content animals, and so on.

Blood types have only a general relationship with any of this.

A+, in fact, is found with a high frequency in Europeans and Sa'ami (these two groups have a 15,000 minimum genetic separation). Chippewa Indians also have a high A+ occurrence.

Otherwise A+ ain't no thang!