Sex-linked genes
this disease is caused by a recessive allele that is found only on the x chromosome. a human female has two x chromosomes. a human male only has 1 x chromosome. therefore, a male needs only one recessives allele to have hemophilia, while a female needs two recessive allele. as a result, hemophilia is much more common in males.
The father is the one who can pass the allele for hemophilia to a daughter. Hemophilia is a recessive X-linked disorder, so the daughter would need to inherit the hemophilia allele from her father.
recessive trait. This means that males are more likely to express hemophilia because they only have one X chromosome. Females can be carriers of the hemophilia allele if they inherit it on one of their X chromosomes.
females have 2 alleles for hemophilia, (X^hX^H) and (X^hX^h) if H is the normal allele and h is the recessive allele for hemophilia
Hemophilia is a recessive allele condition. Men can get hemophilia alot easier than women as the allele is found on the XY Chomosome pair. With men. they do not have the extra "tail" on the Y chromosome compared to the XX with a female. If the person has the recessive allele on the X chromosome and this person is male, they will be a hemophiliac as they do not have a 'pair' allele which could be dominant to stop the condition expressing itself. On a female, if there is a recessive (hemophilia) allele on one of the X chromosomes but on the other is a Dominant (normal) allele then she will be a carrier of the faulty gene but will not suffer from the condition herself. If the female have a recessive (faulty) gene on each of the XX chromosomes, then she will be a sufferer of the disease.
false
Mary's father is normal and has a normal genotype XY while her mother is the carrier of hemophilia and has one X of her genotype infected i.e. she is X*X.
Hemophilia is a X linked recessive disorder. Usually the mother is an unaffected carrier and her son unfortunately receives the X chromosome in which hemophilia is linked to.
The genes associated with Hemophilia A and B are located on the X chromosome, which is one of the 2 sex chromosomes. For males, who have only 1 X chromosome, 1 altered copy of the gene in each cell is sufficient to cause hemophilia. In females, who have 2 X chromosomes, a mutation would have to occur in both copies of the gene to cause hemophilia. Since it is unlikely that females will have 2 altered copies of this gene it is therefor very rare for females to have hemophilia.
the X chromosome
The X chromosome. That's why it's more common in males; females have 2 X chromosomes, but males only have 1. So if a woman has the hemophilia mutation on one of her chromosomes, she probably won't be affected by it.
X*X and XY