can a b- mother and a b- father have a b+ child?

Question

my doctor says that i have a factor in my blood that causes it. one of my children is O- , how does this happen

Answer 1

If you're "-" and the father is "-" then, no, you can't have a "+" child. "+" signifies the presence of the Rh antigen on the cell surface of the red blood cells.

The child either isn't yours or the man you think is the father isn't the father. Get another doctor -- and a lawyer. You need to sue someone.

Answer 2

The short answer is No.
The most important gene to cause Rh + (the + in B+) is the RhD gene that is not just mutated but missing in most Rh - people.
If it were just a single point mutation, then the chance would be 1 in 10,000.
The chance is not even 1 in a billion to recreate a missing gene segment.

Answer 3

It is nothing (much) to do with + or - . Blood Group of a child will be decided as below.

Parents ---------------------------- Child
O + O -------------------------------- O
O + A or A + A --------------------- O or A
O + B or B + B --------------------- O or B
O + AB or A + B --------------------- O or A or B or AB
AB + A or AB + B or AB + AB ------ O or A or B or AB

The above is called a truth table. And the child's blood group can only follow the pattern as above based on the groups that of parents.

Additional information...

AB group is called Universal Acceptor, since blood of any group shall be acceptable incase of emergency.

O group is called universal donar, since O blood can be given to any one incase of Emergency.

The above rules are mostly (generally) true.

Answer 4

i can't understand a word of it maybe you will
http://www.nbc10.com/encyclopedia/6864334/detail.html

http://www.keepkidshealthy.com/newborn/babys_blood_type.html