Is it possible for a child to have 'A' blood type when both parents have 'O' type blood ?

Question

GRANDFATHER HAS TYPE 'O' AND GRANDMOTHER HAS TYPE 'A' THE FATHER AND MOTHER OF THE CHILD HAS TYPE 'O'.

Answer 1

You dont need caps and someone was wrong somewhere on the type of blood.  

Answer 2

Not possible.  Most likely John Edwards is the real father.

Answer 3

Nope.  Type O blood is recessive, meaning that in order to express that blood type, an individual needs to have two copies of the O gene.  Since both parents are known to have two copies of the O gene, the grandparents are irrelevant.  There is no "A" in the previous generation to get passed on to the child.

Of course, this is an oversimplification.  Sometimes a person can possess a gene, but not express it.  In this case, one of the parents could have an AO genotype.  This would normally give them type A blood, *but* if the A allele were "silenced" (other genes regulate themselves like this all the time - it could accidentally happen to the genes coding for blood type) the parent would show type O blood.  They would still possess the A gene, and could pass it on to a child, which would then express it.  

This would be *incredibly* rare, though (like CSI-epidsode rare).  It would be enough to conclude that the child was not their biological offspring, though a more thorough paternity/maternity test would probably be carried out.

Answer 4

No. If both parents have type O blood, the only possible blood type for their children is O.

Answer 5

No. Allele for blood group O is recessive, you'll need two copies to be blood group O. Since neither parent will have an allele for blood group A, the child can only inherit O alleles, and be blood group O.

Answer 6

No.  In order for a child to have type A blood, at least one parent would need to have type A or type AB.