Suppose the human trait for dimples is controlled by a simple dominant and reces

Question

Suppose the human trait for dimples is controlled by a simple dominant and recessive relationship at one locus. You wanted to determine the frequency of people with dimples in the city of Doral. Of the 2500 people you surveyed in downtown Doral, 1712 have dimples. Calculate the frequency of the having dimples -dominant allele, D- and the heterozygous genotype, Dd. Express the frequencies in decimal form rounded to the nearest thousandth. Assume the population in the city of Dora! is in Hardy-Weinberg equilibrium for this trait. 3.

Explanation / Answer

Dimple phenotype = Dominant = DD or Dd

Non-dimple phenotype = Recessive = dd

It is given that the population is in HW equilibrium.

p+q = 1

p2 + 2pq + q2 = 1

Total population = 2500

Since humans are diploid organisms,

Total number of alleles at the given locus = 2500 X 2 = 5000

Number of people with dimple (DD or Dd) = 1712

Number of people without dimple (dd) = 2500 - 1712 = 788

q2 = 788

Frequency of people without dimples = (788/2500)

q2 = 0.3152

q = 0.561

Frequency of DD

p = 1 - 0.561 = 0.438

p^2 = 0.192

Frequency of Dd

2pq = 2 X 0.438 X 0.561

2pq = 0.491

p2 + 2pq + q2 = 1

0.192 + 0.491 + 0.3152 = 0.99 = 1

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.