--- In nursingstudents@yahoogroups.com, "emily_christopher_mom"
<emily_christopher_mom@...> wrote:
>
> Okay this is a personal medical question so I thought that I would
see
> if any of you could help me. If a mother has A positive blood and
a
> baby has O positive blood then what type of blood would the father
have
> to have??
>
> Crystal
>
It's a little complicated. The father could have multiple blood
types. Read on... (or cut & paste this link
http://www.drgreene.com/21_679.html)

Each person receives an A, a B, or an O gene from each parent. In
this system, the A and B genes are co-dominant, and the O gene is
recessive. Thus a person whose genetic type is either AA or AO will
have blood type A, those with genetic type BB or BO will have blood
type B, and only those with genetic type OO will have blood type O.
This means that a child with type O blood could have parents with
type A, type B, or type O blood (but not with type AB). Conversely,
if two parents both have type O blood, all their children will have
type O blood.

Another medically important blood type is described in the Rh
system. These genes were first discovered in the rhesus monkey,
hence the designation Rh. The Rh system is actually far more complex
than the ABO system in that there are 35 different possibilities
that one could inherit from each parent. These, however, are roughly
grouped into positive and negative types. In this system the
positive are dominant over the negative. Thus if your genetic type
is ++ or +-, your blood type will be Rh positive. Only if your
genetic type is -- will you be Rh negative. This means that if both
parents have Rh+ blood with the +- genes, they could have children
who are ++, +-, or --. In other words, their children could be
either Rh positive or Rh negative. Children who are Rh negative can
have parents who are either Rh positive or Rh negative.