A gene has two alleles that are associated with body mass in an additive manner. The table below shows the mean phenotype for each genotype, along with the frequency of each genotype in a population. Use this information to answer the following questions. A1A1 A1A2 A2A2 Mean mass (kg) 50 55 60 Frequency 0.01 0.18 0.81 a) How much does this locus contribute to additive genetic variation? b)A second locus (B) has two alleles (B1 and B2), which are also associated with body mass in an additive manner. Each copy of the B2 allele adds 2 kg of mass. The B2 allele is at a frequency of 0.6 in the same population as the A alleles are found. How much does the B locus contribute to additive genetic variation? c) Assume that these two loci are the only sources of additive genetic variance for body mass. The total phenotypic variance for body mass in the population is 10 kg2. What is the narrow sense heritability (h2) of body mass in this population? d) What is the expected covariance of a child’s phenotype with the parental midpoint phenotype?
Evolutionary Genetics
Evolution is known as continuous changes that occur to adjust organisms in their changing environment over many generations. Various theories have been proposed to illustrate the origin of life and organic evolution. The most accepted one is the theory of natural selection by Charles Darwin. According to his postulate, organisms undergo a struggle for existence due to overproduction. To survive in nature, they acquire variations. The inheritable variations are selected by nature, and it leads to the survival of the fittest.
Phenotype Frequency
The majority of populations have a certain degree of variation in their genetic pools. Scientists can predict the genetic variation happening over time by measuring the amount of genetic variation in a population and these predictions assist them in gaining important insights into the processes that allow organisms to adapt to the environment or to develop into new species over generations. This process is referred to as the process of evolution.
Hardy Weinberg Equilibrium
The frequencies of allele and genotype were maintained constant from one generation to another due to the absence of other evolutionary forces. It is otherwise called the Hardy Weinberg principle the field of population genetics.
A gene has two alleles that are associated with body mass in an additive manner. The table below shows the mean
|
|
A1A1 |
A1A2 |
A2A2 |
|
Mean mass (kg) |
50 |
55 |
60 |
|
Frequency |
0.01 |
0.18 |
0.81 |
a)
How much does this locus contribute to additive
What is the expected covariance of a child’s phenotype with the parental midpoint phenotype?
Since it enables one to quantify the degree to which genetic variables contribute to the observed variation in a trait inside a population, genetic variance is a fundamental term in genetics and heritability studies.
Based on the kinds of genetic interactions impacting the trait, this variance can be further broken down into components, such as additive genetic variance (V_A), dominance genetic variance (V_D), as well as epistatic genetic variance (V_I).
Step by step
Solved in 6 steps
