No,there are two possibilities-blood type A or blood type O (if the parent with blood type A has the genotype AO).To have a child with blood type AB,the parents have to be A and B.
How were the blood types determined? Could the O have been typed wrong?
In theory, it shouldn’t happen, but there are lots of examples of type inheritances that don’t follow the rules. Most of the time, the blood types have been done poorly, but I know of circumstances where that’s unlikely and the patterns still don’t fit the rules.
It is possible – if parrent with with tipe O hase this becouse he/she luck protien thac carry polysacharide chein that determnate bloode tipe (If I am not wrong it is called Bombei sindrome). So he/she can carry allele B but not blood tipe B.
Could be the agglutination is very smooth thus they thought it was O instead of B. Soemtimes it happens here, then we need to examine with miscroscope to see the agglutination.
yes, its all about chances, have you used the punnet square method? its really good for finding chances of charasticts like blood type, hair colour etc.
.
.