I just skimmed through Human Biological Variation today. It was somewhat disappointing, the exploration of topics was often too superficial and I really didn't need a review of what mitosis, meiosis and Hardy-Weinberg Equilibrium were. They do collate some interesting data in the latter portion of the book, but the only one I'd like to pass on is about blood groups. This is one genetic trait which most of us happen to know about our own status in regards to, I'm an A, my father is a B and my mother is an A. But we are often under the impression that this is capricious, and the variation in frequency of the different alleles is a function of random genetic drift. This is not totally true. Below is a copy of table 4.6 from the book: The worldwide frequencies are O at 63%, A at 21% and B at 16%. O is "recessive" in that an individual who is AO expresses A, and someone who is BO expresses B. Since I am an A, and my father is a B, he is probably a BO and I am an AO. The ratios of blood groups derive from, for example: A:O = [A(patients) X O(controls)]/[O(patients) X A(controls)] Stomach cancer, A:O - 1.22 Cancer of cervix, A:O - 1.13 Malignant tumors of salivary glands, A:O - 1.64 Nonmalignant tumoros of salivary glands A:O 2.02 Duodenal ulcers, O:A - 1.35 " ", O:A+B+AB - 1.33 Gastric ulcers, O:A - 1.17 " ", O:A+B+AB - 1.18 Rheumatic disease, A:O - 1.23 Diabetes mellitus, A:O - 1.07 " ", A+B+AB:O - 1.07 Ischemic heart disease, A:O - 1.18 " ", A+B+AB:O 1.17 Thromboembolic disease, A:O - 1.61 " ", A+B+AB:O - 1.60 Also, * A study in Bangladesh has shown an assocation between cholera infection and blood group O. * O have an advantage in syphylis, so if you are a slut, check your blood group! * Mosquitos like the taste of O blood. * There is some evidence that A individuals handle meat better while B prefer carbohydrates. Also, amusingly, B is a good predictor of "ponderality." Anyway, just so you can do the conditional probabilities in your own life....