What possible genotype parent would produce an As gene child?Father's gene is AA, BG O+. Mother's BG is B+. But, I dont know her genotype. Their...

Well it looks like you have two different things going on
here. If the father is AA and the child is As, then the mother contributed the s gene;
we can only give her genotype as "s?" without additional information. For the blood
groups, the blood type ( A, B, AB, or O) is a separate gene than the Rh factor, which
gives you the + or - part of the blood type.

Let's look at
the blood type first. A and B are two proteins that can occur on the outer membranes of
the blood cells, they are part of the body's mechanism of identifying self versus
intruder for the immune system. A person with type A blood has the A protein on his/her
cells, a person with type B blood has the B protein, and a person with type AB has both
the A and B proteins. A type O person has neither of those proteins. The O blood type is
recessive, so in order for the father to be type O he has to have 2 O genes. The mother
is type B, so she has at least one B gene, and we can't be sure about the other - she
could be BB or BO. Their son's genotype is BO, because he got a B gene from the mother
and an O gene from the father.

The Rh factor is yet another
surface protein. If you are Rh+ then you have this protein, if Rh- then you don't. The
gene is dominant, so it only takes one copy to make you Rh+. In this scenario both
parents are Rh+, but we don't know if each has one copy of the Rh gene or two
copies.Either way, the son got a copy of the Rh+ gene from one of them, making him Rh+
also.

I hope this answers your question. I have attached a
couple of links; one is a tutorial about blood groups and types, and the second has a
link (left side of the page) for a blood group calculator that will so the problems out
for you.