Blood type is determined by the combination of three genetic factors, such as A, B and O, and most of them can judge the possible blood type of the baby born in the future according to the blood type of the parents.
The genetic law of blood type is:? A＋A→A、O； ? A＋B→A、B、O、AB； ? A＋O →A、O； ? A＋AB→A、B、AB； ? B＋B→B、O； ? B＋O→B、O； ? B＋AB→B、A、AB； ? O＋O→O； ? O＋AB →A、B； ? AB＋AB→A、B、AB。
There are many types of human blood types, and each blood type system is determined by genetic factors and has immunological characteristics. The most common blood group system is ABO blood group, which is divided into four types: A, B, AB and O; Followed by Rh blood group system, mainly divided into Rh positive and Rh negative; Once again, it is the blood group system of MN and MNS. According to clinical tests at home and abroad, it is found that there are more than 30 kinds of human blood types.
Extended data:
Blood group gene system:
Generally speaking, the 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.
References:
Baidu Encyclopedia-Table of Blood Group Inheritance Rules