What are the offspring of hemophilia?

Answer 1

Hemophilia is passed down from mother to son. It is extremely

rare for a woman to have hemophilia. It is necessary, though, for

a woman to be a carrier of the disorder for her son to acquire this

disorder. Females have two X chromosomes whereas males only

have one. When a boy is born, he takes one X chromosome from

his mother and one Y chromosome from his father. Therefore, he

can only get hemophilia through his mother.

Example One:

Mother(Carrier)+Father(Non-Affected)=50% chance of their son

acquiring the disorder and 50% chance of their daughter being a

carrier.

Example Two:

Mother(Non-Affected)+Father(Hemophiliac)=All sons will be

non-affected and all daughters will be carriers.

Answer 2

In a cross with a mother who carries the allele for hemophilia and a father who does not (normal blood clotting), the genotype of the offspring would be one female who carries the allele, one female who does not carry the allele, one male who does not, and one male who does. This male who the carries the allele would be a hemophiliac.

The phenotype is what a person would see: two normal females, one normal male, and one hemophiliac male.

Answer 3

For x-linked hemophilia, the possible genotypes resulting in hemophilia in an offspring are:

male: XhY

female: XhXh (This almost never happens, and would require the mother to be a carrier - heterozygous (XHXh) - or to have hemophilia herself (XhXh) - and the father to have hemophilia.)

Notice that it is impossible for the male to be heterozygous, so whatever the gene for hemophilia is on his X chromosome is what is expressed. The female can be a carrier (heterozygous), but because she has one dominant allele, she will not have hemophilia.