Patient's question:
NoDoctor's answer:
Blood type is inherited, and a child's blood type is determined by the blood types of the parents. In 1900, modern scientists uncovered the inheritance pattern of ABO blood types, giving rise to the concept of blood types. A person's blood type is determined by the blood type genes from the father's sperm and the mother's egg, and the combination of these genes is called the genotype. In ABO blood types, the O gene is a recessive gene, while A and B are dominant genes. This means that when the O gene is combined with the A or B gene, only the traits of the A or B gene are expressed, resulting in A or B blood types. Moreover, A and B are co-dominant genes; when the A and B genes are combined, both traits are expressed, resulting in AB blood type. Only when the O gene combines with another O gene does it produce O blood type. ABO blood types have six genotypes, but due to the dominance-recessive relationship between genes, the phenotypes are only four: O, A, B, and AB blood types. It is normal for a parent's blood type to differ from their child's, or for siblings from the same parents to have different blood types—this is a phenomenon of ABO blood type inheritance. The inheritance rules of ABO blood types are as follows: If one parent is O-type, they cannot produce AB-type children; if one parent is AB-type, they cannot have O-type children; if the parents' blood types are O-type and AB-type, the child's blood type will either be A or B, and the child will not share the blood type of either parent.