血液中含哪种凝集原或凝集素是由染色体上的A、B、O三个基因所决定的。其中A、B基因是显性基因，即含AA型基因是A型，称纯合子，含O、A型基因也是A型，称杂合子，B型也是这样，其基因型既可为BB型也可为OB型。这样如果父母双方都是O型，其生殖细胞都只能含O基因，其子女也只能 Which agglutinogen or lectin contained in the blood is determined by the three genes A, B and O on the chromosome. The A and B genes are dominant genes, that is, the AA-containing gene is A type, homozygote, O, A type gene is also A type, said heterozygote, B type is also the case, the genotype can be BB type Can also be OB type. So if both parents are O-type, the germ cells can only contain O gene, its children can only