Question

PLEASE ONLY ANSWER QUESTION 2 - Question 1 is included for background information required to answer question 2. I am unsure of how to calculate genotype and phenotype frequencies and want to learn how to do it.

A recent study has determined that there is a significant genetic basis for over-dramatic personalities in humans. When a genotyping test was released for this locus, all the Kardashian sisters decided to take it to figure out if they could blame biology for their infamous dramatic tendencies. Dramaticness (DD) is dominant to calmness (dd).

1. If Robert Kardashian is calm and Kris Jenner is dramatic, what are the possible genotypes and phenotypes for the three Kardashian sisters (Khloe, Kim, and Kourtney)? Answer this question broadly in what the sisters’ potential genotypes or phenotypes could be. List all possible genotypes and phenotypes possible for the sisters. You are not expected to identify individual’s genotype or phenotype in this question.

           

2. If Rob Kardashian Jr. is also calm, what must be Kris Jenner’s genotype?

                 

3. Complete the Punnett square for the cross between Kris Jenner and Robert Kardashian. Show the parent genotypes on the outside of the square.

                                                                                               

                                                           

           

2. Kim Kardashian is married to Kanye West, and the two have three children together. Kim and Kanye are both heterozygous for the dramatic trait. However, Kim is extraverted (EE) while Kanye is introverted (ee) and so demonstrate their drama in different ways. A heterozygous individual for the extraversion trait would be an ambivert--someone perfectly in between the two personality types. Complete the Punnett square for this cross and calculate the possible genotypes and phenotypes for their children along with the frequencies for each.

1. Punnett square: Show the parent genotypes on the outside of the square.

2. Genotypes and genotypic frequencies:

           

3. Phenotypes and phenotypic frequencies:

4. What type of inheritance pattern does the extraversion trait have?

Answer 1

Dramatics (DD) is dominant to calmness (dd) and extraverted (EE) is partially dominant to introverted (ee). The heterozygous individual (Ee) would be an ambivert.

Kim and Kanye are both heterozygous for the dramatic trait. However, Kim is an extravert (EE) while Kanye is an introvert (ee).

So, the genotype of Kim is DdEE and genotype of Kanye is Ddee

1. F₁ progeny is shown in Punnett Square:

		Gametes from Kanye
		De	de
Gametes from Kim	DE	DDEe (Dramatic, ambivert)	DdEe (Dramatic, ambivert)
	dE	DdEe (Dramatic, ambivert)	ddEe (Calm, ambivert)

2. Genotypes are DDEe , DdEe and ddEe

From the Punnett Square,

No. of expected offspring with DDEe is 1

No. of expected offspring with DdEe is 2

No. of expected offspring with ddEe is 1

Total no. of offspring is (1+2+1=4)

Frequency of DDEe is ¼ = 0.25 or 25%

Frequency of DdEe is 2/4 = 0.50 or 50%

Frequency of ddEe is ¼ = 0.25 or 25%

3. Phenotypes are Dramatic, ambivert (DDEe /DdEe) and Calm, ambivert (ddEe)

From the Punnett Square,

No. of Dramatic, ambivert offspring is 3

No. of Calm, ambivert offspring is 1

Total no. of offspring is (3+1=4)

The frequency of Dramatic, ambivert is ¾ = 0.75 or 75%

The frequency of Calm, ambivert is ¼ = 0.25 or 25%

4. The extraversion trait has co-dominance insentience pattern. Two different allele of the extraversion trait (E and e) makes two slightly different proteins. Both alleles influence the extraversion trait so 3 different types of phenotypes (extraverted (EE), introverted (ee) and ambivert (Ee)) are expressed.

Kindly revert for any queries and concerns.