How many men in pedigree have hemophilia?
How many men in pedigree have hemophilia?
Hemophilia is a hereditary (X-linked, recessive) blood disorder that affects the proper clotting of blood. It is a disease that affects males much more frequently (1 in 10,000) than females (1 in 100,000,000). This occurs because a critical blood-clotting gene is carried on the X chromosome.
When working through a pedigree The first thing you need to do is figure out which characteristic is dominant?
When working through a pedigree, the first thing you need to do is figure out which characteristic is dominant – the shaded one or the un-shaded one. Then you need to choose a letter (let’s use A) and begin assigning genotypes. Remember that recessive individuals are always homozygous, so assign their genotypes first.
Which of the following pedigree can be for haemophilia?
In the given pedigree chart the trait for is haemophilia transmitted from father to the son when the father is affected and from mother to the son when the mother is a carrier. Thus, the correct answer is option C.
What is the genotype of a male with hemophilia?
Since this is a recessive disorder, one XH allele will give a normal phenotype. When the offspring do not have a XH and only have the Xh allele/alleles they will have the hemophilia condition. Man’s genotype is XhY.
How do you tell if a pedigree is dominant or recessive?
Determine whether the trait is dominant or recessive. If the trait is dominant, one of the parents must have the trait. Dominant traits will not skip a generation. If the trait is recessive, neither parent is required to have the trait since they can be heterozygous.
How do you know if you have dominant or recessive genes?
The way people write out dominant and recessive traits is the dominant one gets a capital letter and the recessive one a lower case letter. So for eye color, brown is B and blue is b. As I said above, people have two versions of each gene so you can be BB, Bb, or bb–BB and Bb have brown eyes, bb, blue eyes.