Population genetics Flashcards
Gene pool
all alleles at that locus acros the population
Hardy-Weinberg distribution
characterizes the distributions of genotype frequencies of p and q in populations that are not evolving, and is thus the fundamental null model for population genetics.
- used for predicting risks in genetic counseling
mendilian segregation
A dominant allele hides a recessive allele and determines the organism’s appearance. When an organism makes gametes, each gamete receives just one gene copy, which is selected randomly.
Linkage disequilibrium
term coined to describe the non-random association between alleles of genetic loci that lie in proximity to each other.
SNP
Single nucleotide polymorphism
Genetic drift
the change in frequency of an existing gene variant in the population due to random chance. Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation
Effective population size
Ne, is the size of an ideal population, that would give the same amount of drift as the actual population
Population mutation parameter
measures the diversity per nucleotide site that is expected due to the balance between mutation creating new alleles and drift in absence of selection
Genetic bottleneck/ founder effect (island)
Diversity in subsequent generations is reduced, and allele frequencies may differ significantly
epigenetic factors
collection of chemical modifications and molecular processes that can influence gene expression without altering the underlying DNA sequence
Envirommental factors
encompass a wide range of external influences and conditions that can impact an organism’s development, health, and overall well-being.
nonsynonymous substitutions
Nonsynonymous substitutions, also known as non-silent or amino acid-changing substitutions, refer to genetic mutations or changes in DNA sequence that result in a different amino acid being incorporated into a protein during protein synthesis.
synonymous substitutions
Synonymous substitutions, also known as silent or synonymous mutations, refer to genetic mutations or changes in DNA sequence that do not result in any change in the amino acid sequence of the protein.
Selective sweep
phenomenon in population genetics and evolutionary biology that occurs when a specific genetic variant or allele increases in frequency within a population due to positive natural selection
coefficient of selection
quantifies the strength of natural selection acting on a specific genotype or allele in a population, where positive values indicate negative selection (reduced fitness) and negative values indicate positive selection (increased fitness).
assortative mating
nonrandom mating based on phenotypes rather than between relatives
Consanguinity
the kinship of two individuals characterized by the sharing of common ancestor(s
Coefficient of inbreeding
Terms of the probability of identity in state of different pairs of genes
Coefficient of relationship
a measure of the degree of consanguinity (or biological relationship) between two individuals
Negative selection
the natural process by which deleterious alleles are selectively purged from the populatio
Missense mutations
is a DNA change that results in different amino acids being encoded at a particular position in the resulting protein.
Positive selection
the process by which new advantageous genetic variants sweep a population
Heteroplasmy
the existence of more than one extranuclear (mitochondrial or chloroplast) DNA sequence type in a cell, tissue or organism
Mutagens
a chemical or physical agent capable of inducing changes in DNA called mutations.
Base-excision repair
Single-strand break repair
Nucleotide-excision repair
Homologous recombination mediated DNA repair
Nonhomologous end-joining
ttranslesion synthesis
indel
Translocations
inversions
copy number variation
SINEs
LINEs
De novo mutations
Alternative RNA splicing
Innate immune system
Adaptive immune system
Immuglobulins
D-J joining (somatic recombination I)
V-D-J joining (somatic recombination II)
Protein chain combinatorial diversity
Junctional diversity
Somatic hypermutation
