Learn about genetic variation and its role in evolution and biodiversity. Explore mutations, recombination, gene flow, and genetic drift with interactive examples and visualizations.
Genetic variation refers to differences in DNA sequences among individuals within a population. It is the raw material for evolution and is essential for species to adapt to changing environments. Genetic variation arises through mutations, recombination, gene flow, and genetic drift, creating the diversity that allows populations to survive environmental pressures.
Random changes in DNA sequence that create new alleles. Can occur during DNA replication, through environmental factors, or spontaneously.
Exchange of genetic material between homologous chromosomes during meiosis, creating new allele combinations.
Transfer of genetic variants between populations through migration, increasing genetic diversity.
Simulate different types of mutations and their effects on DNA sequences.
Original Sequence:
ATGCGATCGTAGCTAGCTAGC
Mutated Sequence:
_______________
Effect:
No mutation applied yet
Visualize genetic diversity within a population over generations.
Allele Frequency:
0.5 (50% A, 50% a)
heterozygosity:
0.50
Genetic Diversity Index:
0.50
Results:
AA: 0.36
Aa: 0.48
aa: 0.16
Mutation Rate: 1.67e-9 per base pair
Problem: In a population of 1000 individuals, 360 have the genotype AA, 480 have Aa, and 160 have aa. Calculate the allele frequencies.
Solution:
Frequency of A (p) = (2×AA + Aa) / (2×Total individuals)
p = (2×360 + 480) / (2×1000) = (720 + 480) / 2000 = 0.6
Frequency of a (q) = 1 - p = 1 - 0.6 = 0.4
Alternatively: q = (2×aa + Aa) / (2×Total individuals)
q = (2×160 + 480) / 2000 = (320 + 480) / 2000 = 0.4
Problem: A point mutation changes the codon GAG to GUG. What type of mutation is this and what is its potential effect?
Solution:
GAG codes for glutamic acid, while GUG codes for valine. This is a missense mutation where one amino acid is substituted for another.
This specific mutation is responsible for sickle cell anemia, where the altered hemoglobin protein causes red blood cells to become sickle-shaped, affecting oxygen transport.
Problem: In a small population of 20 individuals, the frequency of allele A is 0.5. After a bottleneck event, only 4 individuals survive. What are the possible allele frequencies in the surviving population?
Solution:
With 4 surviving individuals, the possible numbers of A alleles range from 0 to 8 (since each individual has 2 alleles).
Possible frequencies: 0/8=0, 1/8=0.125, 2/8=0.25, 3/8=0.375, 4/8=0.5, 5/8=0.625, 6/8=0.75, 7/8=0.875, 8/8=1.0
This demonstrates how genetic drift can cause significant changes in allele frequencies in small populations.
Genetic Variation: The diversity of alleles within a population, which is the basis for evolution.
Genetic Drift: A mechanism of evolution that causes random changes in allele frequencies, often reducing genetic variation.
Genetic variation is the raw material, while genetic drift is one of the processes that can affect it.
Genetic Variation: The differences in genetic material among individuals in a population.
Natural Selection: The process by which certain traits become more or less common based on their effect on survival and reproduction.
Genetic variation provides the raw material upon which natural selection acts.
Genetic Variation: Differences in DNA sequences among individuals.
Gene Expression: The process by which information from a gene is used to create functional gene products.
Genetic variation can affect gene expression patterns, but they represent different aspects of genetics.
Genetic Variation: The overall diversity of alleles in a population.
Mutation: The source of new genetic variants that contribute to genetic variation.
Mutations are one source of genetic variation, but genetic variation also includes existing alleles.
Save your simulation parameters and results for later analysis.
Load previously saved simulation data to continue your analysis.