If you know the fraction of homozygous recessive individuals in a population, ca

Question

If you know the fraction of homozygous recessive individuals in a population, can you always estimate the allelic and genotypic frequencies for that population? What conditions must be met by the population in order to do this? In a population that is in Hardy-Weinberg equilibrium, the frequency of the d allele is 0.4. What fraction of the population is DD? Why is it important to mention that this population is in Hardy-Weinberg equilibrium? What five conditions must be met for the Hardy-Weinberg equation to predict the genetic makeup of a population accurately? Why do we consider the Hardy-Weinberg prediction be a "null" hypothesis?

Explanation / Answer

9) Allele/gene frequency is the proportion of all alleles at a locus that are of a specified type. If the fraction of homozygous recessive individuals in a population is known, one can easily calculate the allele frequency using the Hardy-Weinberg principle stating, p2+2pq+q2=1.

            A recessive allele doesn't affect a phenotype unless it is homozygous. The persons carrying the homozygous recessive should be able to reproduce and the allele should not be lost to the gene pool of the population.

(10) frequency of d allele is (q) = 0.4

So, frequency of D allele is (p) = 0.6, (p+q=1; p+0.4=1-->0.6)

The fraction of D allele is given by p2+2pq = (0.6)^2+2(0.4*0.6)

=0.36+0.48 = 0.84

The Hardy-Weinberg principle is applicable here because, the frequency value for a recessive allele has been shown and this might be used for idenitying other allelic frequencies.

(11). The Hardy-Weinberg principle models a population without evolution under the following conditions:

(1) no mutations

(2) no immigration/emigration

(3) no natural selection

(4) no sexual selection

(5) a large population

It is described as a null hypothesis because, it is useful for comparing the values from a real population, to describe statistically significant deviations from the equilibrium. It shows that the gene frequencis can change and evolution occurs when the deivation is significant

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---

---

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