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Each person carries two bits of rh imformation, called alleles, and each can be positive or negative.

A person is rh+ if they have at least one positive allele. Only if both their alleles are negative are they considered as rh-.

When two parents have a baby, they each pass one allele on. So if both parent has one positive and one negative allele, and both passed on their negative allele to their baby, then the baby would be rh negative.

The chances of two rh positive parents having a rh negative baby are about 18%.

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Q: Why do rh positive parents have an rh negative baby?
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Rh positive mother a positive baby?

If a person has the Rh factor, then they are positive. If they don't have the Rh factor, they are negative. The Rh factor is dominant, so a mother with it would have an Rh positive baby even if the father is negative for the Rh factor.


Can two o positives make an o negative?

Yes this is true only if both parents are heterozygous positive. This means that the parents genotypes are +- for blood type. + blood type is dominant over - blood type, so this means that one can only have negative blood type if their parents are either heterozygous or homozygous recessive. A helpful tool to finding out the probability for this question would be to use a punnett square. If you used this method you would find out that two heterozygous positive blood type parents have a 25% chance of producing offspring with negative blood type.


Can a child born with rh negative blood type be the offspring of an o positive father?

It depends on the genotype of the Rh+ parent. If that person is heterozygous, then yes there is a 50% chance of an Rh- baby.Father's Group (negative)Mother's Group (positive heterozygous)Rh +Rh -Rh -Rh +, Rh -Rh -, Rh -Rh -Rh +, Rh -Rh - Rh -http://www.bloodbook.com/inherited.htmlIf the positive parent is homozygous, the baby will be positive:Father's Group (negative)Mother's Group (positive homozygous)Rh +Rh +Rh -Rh +, Rh -Rh +, Rh -Rh -Rh +, Rh -Rh + Rh -


What type blood does a negative male and o positive female make?

There's not enough information to give the probable blood groups since no blood group was given for the male. However, an rh negative male and an rh positive female could produce either an rh negative baby or an rh positive baby. The male is definitely homozygous recessive for rh factor, but the female could be homozygous dominant for rh factor, in which case the baby would be heterozygous for rh factor and it would be rh positive. However, if the female is heterozygous for rh factor, there is a 50% chance the baby would be rh positive (heterozygous) and a 50% change the baby would be rh negative (homozygous recessive).


Can parents with a Rh negative and b positive have a child o or a positive?

yes

Related questions

Mother is o positive and father is o positive Does this mean baby will be o positive?

No. There's a small chance the baby will be O negative--if both parents have an Rh negative (recessive) allele, and the baby inherits this allele from both parents, the baby would be Rh negative. But if the baby inherits the Rh positive allele from either parent, the baby will be Rh positive.


Can baby be negative if mom is positive and dad negative?

It takes two rh negative parents to produce an rh negative baby.


Can two parents with A positive blood have an Rh A negative baby?

not chance,but rarely can be.


Can a baby be born with positive blood if both parents are negative?

No. If both parents are Rh negative, they are homozygous recessive for the Rh factor and can only pass on recessive alleles to their children, and a positive Rh factor is a dominant trait.


If the parents are Rh positive could they produce an Rh negative child or just Rh positive offspring?

We are looking for the possible Rh blood types of a baby.Parental information:Mother Rh pos -- can be (++) or (+-) = contributes (+) or (-) geneFather Rh pos -- can be (++) or (+-) = contributes (+) or (-) geneBaby receives one gene from each parent: Baby is Rh (++) = Rh posBaby is Rh (+-) = Rh posBaby is Rh (--) = Rh negTherefore, depending on the exact genetics of the parents, the baby may be Rh positive or negative.


Rh positive mother a positive baby?

If a person has the Rh factor, then they are positive. If they don't have the Rh factor, they are negative. The Rh factor is dominant, so a mother with it would have an Rh positive baby even if the father is negative for the Rh factor.


Can a A positive blood type mother give birth to Rh negative daughter?

Can a child with RH neg blood come from parents that are A positive and A negative


Can a rh positive father have a rhs negative baby?

Yes, it is possible. There are two genetic alleles that together determine whether a person is Rh positive or negative. It is the combination of these alleles within the parents that determine the child's Rh status. In this case, both mother and father are positive so their alleles can only be ++ or +-. The possible combinations are determined by taking one allele from one parent and combining it with an allele of the other until all combinations are made. Positive is the dominant allele so combinations of ++ and +- are considered Rh positive whereas -- combinations are negative. The possible combinations are: ++ which would be an Rh positive baby +- which would be an Rh positive baby -- which would be an Rh negative baby So yes, it is possible.


Can parents have negative and positive Rh children?

CAN children hae positive and negative RH factor blood types


Can both of the parents be RH Neg and still have a healthy child?

Yes. You will occasionally have problems if the mother is Rh negative and the father is Rh positive; if the baby is Rh positive, there is a possibility for complications if the baby's blood poisons the mother. This is pretty rare these days.


Can a parent with A positive and a parent with A negative have an O negative baby?

Yes. The parents' blood types are AO and AO so the baby will be OO. And since at least one parent is Rh+, the child will be Rh+.


Can o positive and a positive parents have o negative child?

Yes. Since the Rh factor is recessive if both parents have a copy of the gene they can have an Rh negative child.