How do you solve a pedigree problem?

Posted on by Muna Meyer

How do you solve a pedigree problem?

Solving Pedigree Analysis in 3 steps

  1. First: Look for Mitochondrial Inheritance.
  2. Second: Look if the gene is Dominant, Recessive.
  3. Third: Look if the disease is X-linked or Autosomal or Y-linked.
  4. Codominant Inheritiance.

How do you calculate pedigree?

Reading a pedigree

  1. Determine whether the trait is dominant or recessive. If the trait is dominant, one of the parents must have the trait.
  2. Determine if the chart shows an autosomal or sex-linked (usually X-linked) trait. For example, in X-linked recessive traits, males are much more commonly affected than females.

Can you be sure of the genotypes of the affected siblings of individual III 3 explain?

Can you be sure of the genotypes of the affected siblings of individual #3? Explain. No, as long as have one copy of the dominant allele, they will have the trait.

What is the relationship between I 2 and III 2?

I-2 and II-2 are parent and offspring/mother and son. 3 generations are shown. I-2 is the affected female. III-2 is the affected male.

Why does individual IV 7 have colorblindness?

Why does individual IV-7 (a female) have colorblindness? This is because since her mother is a carrier of colorblindness and the father is colorblind, then one must be colorblind, for in this cast is the individual IV-7.

Can an individual IV 2 be a carrier?

Name the two individuals that should be marked as carriers of hitchhiker’s thumb. Q. Is it possible for individual IV-2 to be a carrier? Yes, because her parents are carriers.

When working through a pedigree the first thing?

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.

How do you do a pedigree analysis?

Prepare a pedigree chart on the basis of the information collected, using appropriate symbols. Examine the pedigree chart carefully to find out whether the disease is autosomal recessive, autosomal dominant, X-linked dominant or recessive and Y-linked dominant or recessive.

How do you write a pedigree analysis?

Best Practices When Creating a Pedigree Chart

  1. Start your chart. Begin your chart with the father and mother.
  2. Create branches. Make branches coming from the father and mother to each of the children or offspring.
  3. Add generations. As you add generations, label each generation using Roman numerals (I, II, III, and so on).

How do you explain a pedigree chart?

A pedigree chart displays a family tree, and shows the members of the family who are affected by a genetic trait. This chart shows four generations of a family with four individuals who are affected by a form of colorblindness. Circles represent females and squares represent males.