What are the assumptions of Hardy-Weinberg equilibrium?

The Hardy-Weinberg equilibrium relies on several key assumptions to accurately predict genotype frequencies in a population: Random Mating: Individuals in the population mate randomly, without preference for specific genotypes or phenotypes. No Evolutionary Forces: There is no mutation, natural selection, genetic drift, or gene flow affecting allele frequencies. Large Population Size: The population is sufficiently large to prevent random fluctuations in allele frequencies (genetic drift). No Migration: There is no movement of individuals into or out of the population, ensuring allele frequencies remain stable. These assumptions create a theoretical model that serves as a null hypothesis for studying evolutionary changes. If a population deviates from Hardy-Weinberg equilibrium, it suggests that one or more of these assumptions have been violated.

How can you test if a population is in Hardy-Weinberg equilibrium?

To test if a population is in Hardy-Weinberg equilibrium, follow these steps: Calculate Allele Frequencies: Use observed genotype counts to determine p and q . Predict Genotype Frequencies: Plug p and q into the Hardy-Weinberg equation ( p 2 + 2 p q + q 2 = 1 ) to calculate expected genotype frequencies. Compare Observed and Expected Frequencies: Multiply expected frequencies by the total population size to get expected counts. Compare these to observed counts. Statistical Analysis: Use a chi-square test to determine if differences between observed and expected counts are statistically significant. If observed frequencies significantly differ from expected frequencies, the population is not in Hardy-Weinberg equilibrium, indicating non-random mating or evolutionary forces.

22. Evolution of Populations

The Hardy-Weinberg Principle

22. Evolution of Populations

The Hardy-Weinberg Principle: Videos & Practice Problems

Video Lessons Practice Worksheet

Topic summary

The Hardy-Weinberg equation predicts genotype frequencies in a diploid population with two alleles, represented as $p^{2} + q^{2} + 2 p q = 1$ . It assumes random mating and no evolution. By calculating allele frequencies $p + q = 1$ , students can derive genotype frequencies. This model helps identify deviations from equilibrium, indicating potential evolutionary forces at play.

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Introduction to Hardy-Weinberg

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Introduction to Hardy-Weinberg Video Summary

Understanding the Hardy-Weinberg equation is essential for predicting genotype frequencies in a diploid population with two alleles. This equation allows scientists to estimate how common different genotypes will be, based solely on allele frequencies, without needing to track individual mating events. The equation is grounded in two key assumptions: random mating and no changes in allele frequency, which means the population is not evolving.

The Hardy-Weinberg principle states that if a population is in equilibrium, the frequencies of the genotypes can be expressed as follows:

Let p represent the frequency of the dominant allele (A) and q represent the frequency of the recessive allele (a). The relationship between these frequencies is:

p + q = 1

From these allele frequencies, we can derive the expected genotype frequencies:

1. The frequency of homozygous dominant individuals (AA) is given by:

p²

2. The frequency of heterozygous individuals (Aa) is:

2pq

3. The frequency of homozygous recessive individuals (aa) is:

q²

These frequencies must sum to 1, leading to the equation:

p² + 2pq + q² = 1

To apply the Hardy-Weinberg equation, one can use the allele frequencies to calculate the expected genotype frequencies in a population. For example, if the frequency of allele A (p) is known, one can easily find the frequency of allele a (q) using the first equation, and then use these values to determine the expected proportions of each genotype.

This mathematical framework not only provides insights into population genetics but also serves as a foundational concept for understanding evolutionary processes. By practicing various problems involving these equations, students can enhance their proficiency in applying the Hardy-Weinberg principle to real-world scenarios.

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The Hardy-Weinberg Principle Example 1

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The Hardy-Weinberg Principle Example 1 Video Summary

The Hardy-Weinberg principle is a fundamental concept in population genetics that describes how allele frequencies in a population remain constant from generation to generation in the absence of evolutionary influences. This principle is represented mathematically by the equations:

\[p^2 + 2pq + q^2 = 1\]

where:

p = frequency of the dominant allele
q = frequency of the recessive allele
p² = frequency of homozygous dominant individuals
2pq = frequency of heterozygous individuals
q² = frequency of homozygous recessive individuals

In a given population, if the allele frequencies are known, the genotype frequencies can be calculated using these equations. For example, if the frequency of allele p is 0.2 and allele q is 0.8, the calculations would be as follows:

\[p^2 = (0.2)^2 = 0.04\]

\[2pq = 2 \times 0.2 \times 0.8 = 0.32\]

\[q^2 = (0.8)^2 = 0.64\]

These calculations can be repeated for different populations to determine their respective genotype frequencies. For instance, if allele frequencies for another population are 0.4 and 0.6, the calculations yield:

\[p^2 = (0.4)^2 = 0.16\]

\[2pq = 2 \times 0.4 \times 0.6 = 0.48\]

\[q^2 = (0.6)^2 = 0.36\]

Once the genotype frequencies are calculated, they can be graphically represented. The y-axis typically represents genotype frequencies, while the x-axis represents allele frequencies. As allele frequencies change, the corresponding genotype frequencies can be plotted, revealing trends in the population's genetic structure.

In populations at Hardy-Weinberg equilibrium, the graph of genotype frequencies will exhibit specific patterns. For instance, as the frequency of allele p increases, the frequency of homozygous dominant individuals (p²) also increases, while the frequency of heterozygous individuals (2pq) reaches a peak and then declines. Conversely, the frequency of homozygous recessive individuals (q²) decreases as p increases.

These trends illustrate that when allele frequencies are low, homozygous individuals are rare, while higher frequencies of alleles lead to a greater presence of homozygous individuals. Additionally, in a stable population, heterozygotes are expected to be more common than either homozygous genotype, reinforcing the significance of genetic diversity within populations.

Understanding these dynamics is crucial for predicting how populations will respond to environmental changes and for conservation efforts aimed at maintaining genetic diversity.

Problem

In the Hardy-Weinberg equation, what does the term 2pq represent?

The probability of being a homozygote for the first allele.

The probability of being a homozygote for the second allele.

The probability of being a heterozygote.

The combined probability of all genotypes.

Problem

Which of the following statements about the Hardy-Weinberg equation are true?

I) For a gene with two alleles, q² represents the frequency of one of the homozygotes.
II) If p and q both equal 0.5, you expect 50% of the population to be heterozygous.
III) The p² and q² terms will be equal as they both represent the probability of being a homozygote.

I & II only.

II & III only.

I & III only.

I, II, & III.

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Predicting Allele or Genotype Frequencies Using Hardy-Weinberg

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Predicting Allele or Genotype Frequencies Using Hardy-Weinberg Video Summary

The Hardy-Weinberg principle is a fundamental concept in population genetics that allows for the prediction of allele and genotype frequencies within a population under specific conditions. To effectively utilize this principle, it is essential to understand the assumptions that must be met for a population to be in Hardy-Weinberg equilibrium. These assumptions include random mating and the absence of evolutionary influences, such as natural selection, mutation, migration, or genetic drift.

When approaching problems related to Hardy-Weinberg, it is crucial to remember the key equations. The first equation pertains to allele frequencies, expressed as:

$ p + q = 1 $

Here, $ p $ represents the frequency of one allele, while $ q $ represents the frequency of the alternative allele. Together, they account for all alleles in a population consisting of two alleles.

The second equation, known as the Hardy-Weinberg equation, is used to calculate genotype frequencies:

$ p^2 + 2pq + q^2 = 1 $

In this equation, $ p^2 $ denotes the frequency of the homozygous dominant genotype, $ 2pq $ represents the frequency of the heterozygous genotype, and $ q^2 $ indicates the frequency of the homozygous recessive genotype. The sum of these frequencies equals 1, reflecting all possible genotypes in the population.

To solve Hardy-Weinberg problems, start by identifying the information provided. You may be given values for $ p $, $ q $, or one of the genotype frequencies (e.g., $ p^2 $ or $ q^2 $). Determine which variable the problem requires you to find, whether it be $ p $, $ q $, or $ 2pq $. From there, basic arithmetic or algebra can be employed to solve for the unknowns.

Additionally, it is important to recognize the relationship between genotypes and phenotypes. Genotypes directly influence phenotypes, with dominant alleles masking the expression of recessive alleles. For instance, individuals with genotypes $ AA $ (homozygous dominant) and $ Aa $ (heterozygous) will exhibit the dominant phenotype, while only those with the genotype $ aa $ (homozygous recessive) will display the recessive phenotype. If a problem requires reporting results in terms of phenotypes, a conversion based on these dominance relationships may be necessary.

By mastering these concepts and equations, students can confidently tackle a variety of problems related to allele and genotype frequencies using the Hardy-Weinberg principle.

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A. Calculating Genotype Frequency from Allele Frequency

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A. Calculating Genotype Frequency from Allele Frequency Video Summary

The Hardy-Weinberg principle is a fundamental concept in population genetics that allows us to calculate genotype frequencies from known allele frequencies. The key equations involved in this principle are:

1. **Genotype Frequency of Homozygous Dominant (AA)**: $ p^2 $ 2. **Genotype Frequency of Heterozygotes (Aa)**: $ 2pq $ 3. **Genotype Frequency of Homozygous Recessive (aa)**: $ q^2 $

In this context, $ p $ represents the frequency of the dominant allele (A), and $ q $ represents the frequency of the recessive allele (a). The relationship between $ p $ and $ q $ is defined by the equation $ p + q = 1 $.

For example, if the frequency of the A allele is 0.2 (thus $ p = 0.2 $) and the frequency of the a allele is 0.8 (thus $ q = 0.8 $), we can calculate the genotype frequencies as follows:

1. **Homozygous Dominant (AA)**: \[ p^2 = (0.2)^2 = 0.04 \]

2. **Heterozygotes (Aa)**: \[ 2pq = 2 \times 0.2 \times 0.8 = 0.32 \]

3. **Homozygous Recessive (aa)**: \[ q^2 = (0.8)^2 = 0.64 \]

After calculating these frequencies, we find:

- Frequency of AA: 0.04 - Frequency of Aa: 0.32 - Frequency of aa: 0.64

To ensure the calculations are correct, we can verify that the sum of all genotype frequencies equals 1:

$ 0.04 + 0.32 + 0.64 = 1.00 $

This confirms that the calculations are accurate, and the genotype frequencies derived from the allele frequencies are consistent with the Hardy-Weinberg equilibrium. Understanding these calculations is essential for analyzing genetic variation within populations and predicting how allele frequencies may change over time.

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B. Calculating Allele Frequency from a Genotype Frequency

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B. Calculating Allele Frequency from a Genotype Frequency Video Summary

The Hardy-Weinberg equation is a fundamental principle in population genetics that allows for the calculation of allele frequencies from genotype frequencies. To work backwards from genotype to allele frequency, we can follow a systematic approach using the equations:

1. The basic relationship between allele frequencies is given by the equation: $ p + q = 1 $, where $ p $ represents the frequency of the dominant allele and $ q $ represents the frequency of the recessive allele.

2. The Hardy-Weinberg principle also provides a formula for genotype frequencies: $ p^2 + 2pq + q^2 = 1 $. Here, $ p^2 $ represents the frequency of homozygous dominant individuals, $ 2pq $ represents the frequency of heterozygous individuals, and $ q^2 $ represents the frequency of homozygous recessive individuals.

To illustrate this process, consider a population where 1% of individuals are homozygous recessive (little a, little a). This means that $ q^2 = 0.01 $. To find $ q $, we take the square root of $ q^2 $: $ q = \sqrt{0.01} = 0.1 $, indicating that the frequency of the little a allele is 10%.

Next, we can find $ p $ using the relationship $ p + q = 1 $. Substituting the value of $ q $ gives us: $ p + 0.1 = 1 $. Solving for $ p $ results in $ p = 1 - 0.1 = 0.9 $, meaning the frequency of the dominant allele (big A) is 90%.

In summary, for this population, the frequency of the big A allele is 0.9 (or 90%), and the frequency of the little a allele is 0.1 (or 10%). This foundational understanding of allele frequencies can be further applied to calculate the expected frequencies of different genotypes within the population, such as homozygous dominant and heterozygous individuals, using the Hardy-Weinberg equations.

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C. Calculating Allele Frequency from Phenotype Frequency

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C. Calculating Allele Frequency from Phenotype Frequency Video Summary

To calculate allele frequency from phenotype frequency using the Hardy-Weinberg equation, it is essential to first convert phenotype frequencies into genotype frequencies. This process can be particularly challenging in cases of simple dominance, where two genotypes can result in the same dominant phenotype. For instance, the dominant phenotype can arise from either the homozygous dominant genotype (AA) or the heterozygous genotype (Aa), while the recessive phenotype is solely represented by the homozygous recessive genotype (aa).

The Hardy-Weinberg principle provides a framework for understanding these relationships through the equations: p + q = 1 and p² + 2pq + q² = 1, where p represents the frequency of the dominant allele (A) and q represents the frequency of the recessive allele (a). The frequency of the dominant phenotype can be expressed as the sum of the frequencies of the homozygous dominant and heterozygous genotypes: p² + 2pq.

For example, if 64% of a population displays the dominant trait, this can be represented as 0.64 = p² + 2pq. To find the frequency of heterozygotes (2pq), additional steps are required. First, we can determine the frequency of the recessive genotype (q²) by rearranging the Hardy-Weinberg equation:

p² + 2pq + q² = 1

Substituting the known value:

0.64 + q² = 1

Solving for q² gives us q² = 1 - 0.64 = 0.36. Taking the square root of both sides yields q = √0.36 = 0.6.

Next, we can find p using the equation p + q = 1:

p + 0.6 = 1

Thus, p = 1 - 0.6 = 0.4.

With both p and q determined, we can now calculate the frequency of heterozygotes:

2pq = 2 × 0.4 × 0.6 = 0.48.

Finally, to express this frequency as a percentage, we convert 0.48 to 48%. Therefore, if 64% of individuals in a population display the dominant trait, we can predict that 48% of the population will be heterozygous.

This method illustrates the importance of systematically applying the Hardy-Weinberg equations to derive allele and genotype frequencies from phenotype data, reinforcing the interconnectedness of genetic principles in population genetics.

Problem

Imagine a population of cats where one gene codes for eye color. The E allele codes for yellow eyes and is dominant. The e allele codes for green eyes and is recessive. The frequency of the E allele is 0.6, and the frequency of the e allele is 0.4. Assuming the population is in Hardy-Weinberg equilibrium, what percent of the population will have green eyes?

36%

24%

16%

48%

Problem

Sickle cell anemia is a recessive trait. In Nigeria, it is estimated that 2.4% of the population is born with sickle cell anemia. Heterozygotes for the sickle cell allele are said to have the sickle cell trait and have few sickle cell symptoms. Assuming that the population is in Hardy Weinberg equilibrium for the sickle cell gene, what percentage of the population would you expect to have the sickle cell trait?

~71.4%

~13%

~15.5%

~26%

Problem

PTC is a chemical that elicits a bitter taste response in some people. The ability to taste PTC depends on the presence of the PTC-tasting allele. Individuals with at least one copy of the PTC-tasting allele taste PTC as bitter. It is estimated that about 70% of the population taste PTC. Assuming that the population is in Hardy-Weinberg equilibrium for this trait, what percent of the population would you expect to be heterozygous for this trait?

~42%

~49%

~45%

~54%

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Testing if a Population is in Hardy-Weinberg Equilibrium

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Testing if a Population is in Hardy-Weinberg Equilibrium Video Summary

To determine if a population is in Hardy-Weinberg Equilibrium, we compare the actual genotype frequencies observed in a sample to the expected frequencies derived from the Hardy-Weinberg principle. This principle serves as a null model in population genetics, indicating what allele frequencies would look like if no evolutionary forces were acting on the population. If the observed frequencies significantly differ from the expected frequencies, it suggests that one or more of the assumptions of Hardy-Weinberg are violated, indicating potential non-random mating or evolutionary changes such as natural selection.

To assess Hardy-Weinberg Equilibrium, follow these steps:

1. **Calculate Allele Frequencies**: Determine the frequencies of the dominant allele (p) and the recessive allele (q). The formula for calculating p is:

\[ p = \frac{2 \times \text{(number of homozygotes for dominant allele)} + \text{(number of heterozygotes)}}{2 \times \text{(total number of individuals)}} \]

For q, since p + q = 1, it can be calculated as:

\[ q = 1 - p \]

2. **Use the Hardy-Weinberg Equation**: Plug the values of p and q into the Hardy-Weinberg equation to find the expected genotype frequencies:

\[ p^2 \] for homozygotes of the dominant allele,

\[ 2pq \] for heterozygotes, and

\[ q^2 \] for homozygotes of the recessive allele.

3. **Calculate Expected Counts**: Multiply the expected frequencies by the total number of individuals in the sample to find the expected counts for each genotype.

4. **Compare Observed and Expected Counts**: Finally, compare the observed counts from the sample to the expected counts. If there is a significant difference, it indicates that the population is not in Hardy-Weinberg Equilibrium.

For example, consider a population with 250 homozygotes for the dominant allele (AA), 100 heterozygotes (Aa), and 150 homozygotes for the recessive allele (aa). The total number of individuals is 500. The allele frequencies can be calculated as follows:

\[ p = \frac{2 \times 250 + 100}{2 \times 500} = \frac{600}{1000} = 0.6 \]

\[ q = 1 - p = 0.4 \]

Next, using these frequencies:

\[ p^2 = 0.6^2 = 0.36 \]

\[ 2pq = 2 \times 0.6 \times 0.4 = 0.48 \]

\[ q^2 = 0.4^2 = 0.16 \]

Multiplying these by the total number of individuals gives:

Expected AA: \[ 0.36 \times 500 = 180 \]

Expected Aa: \[ 0.48 \times 500 = 240 \]

Expected aa: \[ 0.16 \times 500 = 80 \]

Comparing these expected counts to the observed counts (250 AA, 100 Aa, 150 aa), it is evident that the population is not in Hardy-Weinberg Equilibrium, as the observed counts do not match the expected counts. This discrepancy suggests that either non-random mating or evolutionary processes are influencing the allele frequencies in this population.

Problem

In a population of glass frogs (Hyalinobatrachium munozorum) you collect 200 individuals. Of those, you determine that 160 are homozygous for the H allele, 10 are homozygous for the h allele, and 30 are heterozygous. Is this population in Hardy-Weinberg equilibrium? If not, why not?

Yes. The population is in Hardy-Weinberg equilibrium.

No. There are more heterozygotes than predicted by the Hardy-Weinberg equation.

No. There are fewer HH homozygotes than predicted by the Hardy-Weinberg equation.

No. There are more HH homozygotes than predicted by the Hardy-Weinberg equation.

Problem

Jorge and Claire are given the following data on fur density in red pandas at zoos in the United States. Is the following population in Hardy-Weinberg equilibrium?

160 homozygous for the F allele, 137 heterozygotes, and 29 homozygous for the f allele.

Yes, the population is in Hardy-Weinberg equilibrium.

No, we would expect there to be more heterozygotes in the population.

No, we would expect there to be more ff homozygotes in the population.

No, we would expect there to be more FF homozygotes in the population.

Dig Deeper into The Hardy-Weinberg Principle

The Hardy-Weinberg principle predicts genotype frequencies in a non-evolving population with two alleles.

Key Terminology

Alleles: Different versions of a gene found at the same locus on homologous chromosomes.
Genotype: The genetic makeup of an organism, specifically the combination of alleles it carries.
Phenotype: The observable traits or characteristics of an organism, often influenced by genotype.
Random Mating: A mating pattern where all individuals have an equal chance to mate, ensuring allele mixing.
Evolution: A change in allele frequencies in a population over time.
Hardy-Weinberg Equilibrium: A theoretical state where allele and genotype frequencies remain constant across generations in the absence of evolutionary forces.
Dominant Allele: An allele that expresses its phenotype even when heterozygous with a recessive allele.
Recessive Allele: An allele whose phenotype is masked in the presence of a dominant allele.
Homozygous: Having two identical alleles for a particular gene (e.g., big A big A or little a little a).
Heterozygous: Having two different alleles for a gene (e.g., big A little a).
Allele Frequency: The proportion of a specific allele among all alleles for a gene in a population.
Genotype Frequency: The proportion of individuals with a particular genotype in a population.

Real-World Applications

Conservation biologists use the Hardy-Weinberg principle to assess whether endangered species populations are evolving or maintaining genetic diversity, which is crucial for their survival.
Medical researchers apply this principle to predict the frequency of carriers for genetic diseases in human populations, aiding in genetic counseling and disease prevention strategies.
Population geneticists use Hardy-Weinberg equilibrium as a null model to detect evolutionary forces such as natural selection, gene flow, or nonrandom mating in wild populations.

Important Formulas & Equations

Allele frequency equation: $p + q = 1$ where $p$ is the frequency of the dominant allele and $q$ is the frequency of the recessive allele.
Genotype frequency equation (Hardy-Weinberg equation): $p^2 + 2pq + q^2 = 1$ where $p^2$ is the frequency of homozygous dominant, \$2pq$ is the frequency of heterozygotes, and $q^2$ is the frequency of homozygous recessive individuals.

Common Misconceptions

Thinking that Hardy-Weinberg equilibrium means populations never evolve — actually, it describes a theoretical baseline where no evolution occurs, but real populations often deviate due to evolutionary forces.
Assuming genotype frequencies always equal allele frequencies — genotype frequencies depend on allele frequencies but are calculated differently using the Hardy-Weinberg equation.
Believing that dominant alleles are always more common — dominance affects phenotype expression, not allele frequency, which can vary widely in populations.
Confusing phenotype frequency with genotype frequency — especially in simple dominance, two genotypes (homozygous dominant and heterozygous) can produce the same dominant phenotype.
Ignoring the assumptions of random mating and no evolution — these are critical for Hardy-Weinberg predictions; violating them means the population is evolving or mating nonrandomly.

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The Hardy-Weinberg equation is a mathematical model used in population genetics to predict genotype frequencies in a diploid population with two alleles. The equation is expressed as:

p^{2} + 2 p q + q^{2} = 1

Here, $p$ represents the frequency of one allele, and $q$ represents the frequency of the other allele. The equation assumes random mating and no evolutionary forces (e.g., mutation, selection, migration). It predicts the proportion of homozygous dominant ( $p^{2}$ ), heterozygous ( $2 p q$ ), and homozygous recessive ( $q^{2}$ ) individuals in a population.

The Hardy-Weinberg equilibrium relies on several key assumptions to accurately predict genotype frequencies in a population:

Random Mating: Individuals in the population mate randomly, without preference for specific genotypes or phenotypes.
No Evolutionary Forces: There is no mutation, natural selection, genetic drift, or gene flow affecting allele frequencies.
Large Population Size: The population is sufficiently large to prevent random fluctuations in allele frequencies (genetic drift).
No Migration: There is no movement of individuals into or out of the population, ensuring allele frequencies remain stable.

These assumptions create a theoretical model that serves as a null hypothesis for studying evolutionary changes. If a population deviates from Hardy-Weinberg equilibrium, it suggests that one or more of these assumptions have been violated.

To calculate allele frequencies from genotype frequencies, you work backwards using the Hardy-Weinberg equation. For example, if you know the frequency of homozygous recessive individuals ( $q^{2}$ ), you can find $q$ by taking the square root:

q = \sqrt{q^{2}}

Once $q$ is known, use the equation $p + q = 1$ to find $p$ . For example, if $q$ = 0.2, then $p$ = 1 - 0.2 = 0.8. These allele frequencies can then be used to predict genotype frequencies using the Hardy-Weinberg equation.

To test if a population is in Hardy-Weinberg equilibrium, follow these steps:

Calculate Allele Frequencies: Use observed genotype counts to determine $p$ and $q$ .
Predict Genotype Frequencies: Plug $p$ and $q$ into the Hardy-Weinberg equation ( $p^{2} + 2 p q + q^{2} = 1$ ) to calculate expected genotype frequencies.
Compare Observed and Expected Frequencies: Multiply expected frequencies by the total population size to get expected counts. Compare these to observed counts.
Statistical Analysis: Use a chi-square test to determine if differences between observed and expected counts are statistically significant.

If observed frequencies significantly differ from expected frequencies, the population is not in Hardy-Weinberg equilibrium, indicating non-random mating or evolutionary forces.

Hardy-Weinberg equilibrium is significant in population genetics as it provides a null model to study evolutionary changes. It predicts genotype frequencies under the assumption of random mating and no evolutionary forces, allowing researchers to identify deviations caused by factors like natural selection, genetic drift, mutation, or migration. By comparing observed data to Hardy-Weinberg expectations, scientists can infer whether a population is evolving and identify the mechanisms driving these changes. Additionally, the model helps in understanding allele and genotype dynamics, estimating carrier frequencies for genetic disorders, and studying the impact of genetic variation on populations.

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The Hardy-Weinberg Principle: Videos & Practice Problems

Introduction to Hardy-Weinberg

Introduction to Hardy-Weinberg Video Summary

The Hardy-Weinberg Principle Example 1

The Hardy-Weinberg Principle Example 1 Video Summary

In the Hardy-Weinberg equation, what does the term 2pq represent?

Predicting Allele or Genotype Frequencies Using Hardy-Weinberg

Predicting Allele or Genotype Frequencies Using Hardy-Weinberg Video Summary

A. Calculating Genotype Frequency from Allele Frequency

A. Calculating Genotype Frequency from Allele Frequency Video Summary

B. Calculating Allele Frequency from a Genotype Frequency

B. Calculating Allele Frequency from a Genotype Frequency Video Summary

C. Calculating Allele Frequency from Phenotype Frequency

C. Calculating Allele Frequency from Phenotype Frequency Video Summary

Testing if a Population is in Hardy-Weinberg Equilibrium

Testing if a Population is in Hardy-Weinberg Equilibrium Video Summary

In a population of glass frogs (Hyalinobatrachium munozorum) you collect 200 individuals. Of those, you determine that 160 are homozygous for the H allele, 10 are homozygous for the h allele, and 30 are heterozygous. Is this population in Hardy-Weinberg equilibrium? If not, why not?

Jorge and Claire are given the following data on fur density in red pandas at zoos in the United States. Is the following population in Hardy-Weinberg equilibrium?

160 homozygous for the F allele, 137 heterozygotes, and 29 homozygous for the f allele.