Hereditary rules of blood type genes
Human blood is divided into four types: A, B, AB, and O. Each type of blood contains different antigens and antibodies. The genetic rules of blood type are mainly controlled by two genes: ABO gene and Rh gene. Among them, the ABO gene determines the type of blood type, and the Rh gene determines the positive and negative. Rh-negative people will only have an antibody reaction with Rh-positive people under special circumstances such as blood transfusions.
There are two ABO genes in each person, inherited from the mother and father. Each gene is present on a set of 23 chromosomes. According to the laws of genetics, A and B generally show a certain coexistence relationship, and o genes are often rarer than A and B. An individual with two A genes can only produce type A blood, an individual with two B genes can only produce type B blood, an individual with A and B together will produce type AB blood, and an individual without A or B will produce type O. Blood type.
The principle of determining paternity through blood type
The basic principle of identifying parent-child relationships through blood types is the law of inheritance. The genes of the ancestors are included in the offspring. For example, children with the four blood types A, B, AB, and O will not produce other blood types. In the process of identifying blood relationships, children or possible relatives with the smallest blood types among A, B, AB, and O are generally selected for matching tests.
If during the test, the father\’s blood type is A, the mother\’s blood type is B, and the child\’s blood type is O, it seems that the child exceeds the possibility of both A and B genes. However, since each person has two ABO genes, the blood type of the parents may be AO or BO type, and type O blood is generated by the genome of both parents with the o gene. If it is known that the i-position blood type gene of the father or mother is o, we can clearly understand the possible genome of the child, that is, we can basically conclude that there is indeed a kinship relationship between the child and the parents.
The possibility of misjudgment exists
Although blood type is a feasible method to determine paternity, there is also the possibility of misjudgment. For example, if the genome of a person with type A blood is type AO and the genome of another person with type B blood is type BO, the children of these two people may have type O blood. Therefore, compared with DNA paternity testing, the accuracy of blood type paternity testing will be slightly less.
Practical application
Despite limitations in the accuracy of blood group paternity testing, this testing method still has a wide range of practical applications. Around the world, many judicial bodies, government departments and private institutions rely on blood typing to determine paternity to resolve disputes and disputes. In addition, doctors will also use blood type to identify paternity to diagnose certain diseases or determine the relationship between pregnant women and newborns.
Summary
Blood type paternity testing is a testing method often used by private and official institutions. It tests the blood types of parents and children based on the genetic rules of blood type to determine the possibility of paternity. Although the accuracy of blood group identification of paternity is slightly less than that of DNA testing, it still plays an important role in practical applications.location and can be used with other screening and relatedness testing methods.
