Scientific research has found that there are three genetic genes that control human ABO blood type: IA, IB and I. Among them, IA and IB are dominant to I, and there is no obvious and implicit relationship between IA and IB. That is to say: the genetic composition of type A blood can be IAIA or IAI; The genetic composition of type B blood can be IBIB or ibi; The genetic composition of AB blood is IAIB；; The genetic composition of type O blood is ii.
Usually, the population can be divided into four blood groups by using only two antisera, namely anti-A and anti-B serum.
Extended data:
Blood type is unchanged for life. Human blood types are usually divided into four types: A, B, O and AB. Blood group inheritance relies on chromosomes in cells. There are 23 pairs of chromosomes in human cells, and each pair of chromosomes consists of two single chromosomes, one from the father and the other from the mother.
The main component of chromosome is deoxyribonucleic acid, which determines genetic traits and functions, that is, DNA, which people often say. DNA can be divided into many small segments, each of which has specific genetic traits and functions. These small segments are called genes. A small fragment of DNA in the same position on two single chromosomes in a pair of chromosomes is called allele.
The gene locus of ABO blood group system is on chromosome 9. Human ABO blood group is controlled by three genes, A, B and O, but there are only two ABO system genes on the ninth chromosome in each human cell, which are a pair of alleles in AO, AA, BO, BB, AB and OO, in which A and B genes are dominant genes and O gene is recessive gene.
Baidu Encyclopedia-Blood Group System