Can an O + (positive) mom and a B+ (positive) dad, have a B - (negative) child?

Answer 1

It is possible. All human had a double duplicate of the same gene, duploid. eg: gene for blood type. Since mom blood is O+ that means she got both O blood gene, it might be O+:O+ or O+:O-.

As for the dad, Since he is B+, that means his gene could have B+:B+ or a B+:B- genes or even B+:O+/-

However egg and sperm cell consisted of haploid chromosome (single chromosome) because of the meiosis process. So some of mom egg cell might contain only O+ and some O-. Same thing happen for dad's sperm which might consist of B+ and some B-.

So if B+ sperm fertilize O+ egg we got B+ baby.
If B+ sperm fertilize O- egg we still got B+ baby (because O and -ve are recessive gene and B+ is dominant gene)
Same thing happen if B- sperm fertilize O+ egg; we still got B+ baby.

If B- sperm fertilize O- egg, we will get B- baby.

However there is still chance for the baby to be O+/- is the father is a B+:O+/- , since O+/- sperm fertilize O+/- egg will produce O-/+ baby.

So based on the dominant and recessive behavior of genes we can deduce that there is 1/8 of a change the baby will be B-, 1/4 of chance it might be O-/+ and 5/8 chance it will be B+

Answer 2

Absolutely. The ABO blood groups are determined based upon the presence or absence of the A antigen or the B antigen. When neither are present the person is type O. THey are known as co-dominant, so if you have one gene for A and the other gene is for B then you are type AB. The Rh factor also depends upon different antigens in which the Rh + antigen is dominant. So, if you are Rh + / Rh - then you are Rh +:

As follows for Rh:
+ / + = +
+ / - = +
- / - = -

The type O Mom has no ABO antigens and the type B Dad must be heterozygous for B and O. Both of them must be heterozygous for Rh +, so they would both be + / -........

So Mom = O / O :: + / -
and Dad = B / O :: +/ -

Their children can be either type B+, type B -, type O + or type O -.

Answer 3

Yes. Rh-negative factor is recessive and both parents have to carry the gene for the child to have it. If 2 Rh-positive parents have an Rh-negative child, then that is proof that both parents carry the Rh-negative gene.

Answer 4

Yes
the genotype for you would be
OO +- expressed as Opos
The genotype for him could be
BB +- or BO +-
You can only give the O gene and either + or - Rh
He can give B or possibly O gene and either + or - Rh
His B gene (with your O gene) and an - Rh gene from both of you will result in a B- child

Answer 5

Yes it is possible. The lack of RH factor (RH-) is a recessive trait and it is very possible for two RH+ parents to both carry the recessive trait. If both parents carry the trait there is a roughly 1 in 4 chance that a child will be RH-.

Answer 6

If both parents are +/-, there would be a 25% chance of having a - child.

Answer 7

the mom and dad must have +,- genes, and then both of their genes must combine so that the child has -,- genes (I'm a living example!)

sorry, can't be to specific... its been to long since I took a biology class.

Answer 8

Yes,don't you worry.Because of the fact that + is dominant and if one your grandmother or grandfather on each side(mother and father's) was negative,then each of your parents carry +/- genotype,and chances are only 25%,but yes if you inherited both -/- genes from each of your parents.

Answer 9

no..if both parents r Rh+ then all their children should be Rh+ coz it depends on the presence or absence of the D gene..and there is no d gene.
about the one that said that his son is Rh - although he and his wife are +s...i think he has to look for the real father!!!

Answer 10

my doctor says no but i dont think he knows what hes talking about im 0+ and my sons father says hes 0+ but my son is A- and my father was A- and so was every one in his family