I. Multiple Alleles
Most genes exist in populations in more than two allelic forms.
EX. ABO blood groups in human population:
Four possible phenotypes for one character:
A, B, AB, or O type.
A, B, refer to two carbohydrates on the surface of red blood cells.
A: A substance alone on the surface of RBC.
B: B substance alone on the surface of RBC.
AB: A and B substance, both exist on the
surface of RBC.
O: Neither A nor B substance exist on the
surface of RBC.
IA: code for the production of A substance.
IB: code for the production of B substance.
i: giving rise to neither A or B sunstance.
ii: receive homozygous.
IA and IB alleles are codominant, both are
expressed in the AB phenotype, and both are dominant to the i allele.
Six genotypes are possible to control ABO character.
|Phenotype group||Genotype||Antigen||Antibodies present
in blood serum
|O||ii||No||a + b|
|A||IA IA IAi||A||b|
|B||IB IB IBi||B||a|
|AB||IA IB||A B||no|
Matching compatible blood groups is critical for blood transfusions.
O type can be a universal blood donor.
AB type can receive blood from A type, B type and O
Pseudoscience: Blood type and Character (Donít believe it)
The personalities of each blood type. Mr.Masahito and Toshitaka Nomi (November 23, 1997)
|Type O||Strongly purpose-oriented. Straight desire. Conscious of powerrelationship. Know how to take chances. Dislike to be subordinate.Expressive.|
|Type A||Considerate about everything. Prefer peaceful human relations.Slow to trust people. Observe social rules and customs.Regard social orderas important Restrain action and expression|
|Type B||Dislike restrictions and one's own way. Non-stereotyped action.Non-stereotyped thinking. Self-conscious and not warped expressions. Makesless distinction of things. Not conscious of circumstances. Don't caresocial rules and customs.|
|Type AB||Rational thinking. Good critic and analyst. To participateand contribute to the society. Good at adjusting human relations. Hopeto be in harmony with the society. Feels distant from the society.|