hi tom! i'm writing an article for teenagers, and am giving a very introductory picture of the blood type diet. can you give me a brief description of how, if at all, your rh factor affects your metabolism or food choices? it would really help me (and the readers)!

thanks so much,
adina

In the Rhesus blood group the main antigens are C, D, E, c and e (capital letters and lower case letters are different antigens). The Rhesus antigens come from two adjacent gene loci, the RHD gene which encodes the D antigen and the RHCE gene which encodes both the C and E antigens. There is no d antigen: Rhesus "d" signifies the absence of the D antigen (the RHD gene is usually non-functional or null), and that person is described as Rhesus (D) negative. Similar to non-secretor status, Rhesus negative is traditionally a "recessive" phenotype, which means in practice that if an individual has no functional Rhesus (D) genes, they are classed as Rhesus negative, but inheriting at least one Rhesus (D) gene will give that person the Rhesus (D) positive phenotype. The Rhesus negative phenotype is generally less common than Rhesus positive. Unlike the ABO blood group antigens, the resulting Rhesus blood group antigen is limited to the red blood cells.

Rhesus D incompatibility is best known as the main cause of newborn fatal blood reactions in the children of Rhesus negative women. Lesser known associations with the Rhesus blood group system are Natural Killer Cell (immune system) activity, transport of ammonia in the kidney and susceptibility to urinary tract tumours, myasthenia gravis, ovarian cysts and tumours, and spinal osteochondrosis. Offspring of a Rhesus positive mother may be more prone to hearing loss.

The question of Rhesus blood group significance is often asked in relation to the Blood Group Diet, but the Rhesus factor takes on a new and greater significance with The GenoType Diet: Rhesus negative phenotype can make a difference to individuals in both systems.

In Live Right 4 Your Type, individuals with Rhesus negative phenotype will find that there are specific recommendations for frequency of eating certain food groups: fewer portions of grain (blood groups A, B and O), fruit (blood group A), and more protein (blood groups B and O).

For an individual's GenoType, being Rhesus negative can mean the difference between being one GenoType or another. The GT4 Explorer is often Rhesus negative, which can change the entire diet and lifestyle advice for that individual.