Population Genetics and Statistical Analysis in Forensics

Vocabulary flashcards for studying key concepts in Population Genetics and Statistical Analysis in Forensics.

Mendelian Genetics

The study of how genes and traits are inherited from one generation to another.

Law of Equal Segregation

Mendel’s first law stating that alleles segregate equally into gametes.

Gametes

Reproductive cells (sperm and oocytes) that contain only one allele from each gene pair.

Law of Independent Assortment

Mendel’s second law that states the segregation of one gene does not affect the segregation of another gene.

Product Rule

The probability of two independent events occurring simultaneously is the product of their individual probabilities.

Population Genetics

The study of the distribution and change of allele frequencies under the influence of evolutionary forces.

Allele Frequency

The proportion of a specific allele among all allele copies in a population.

Genotype Frequency

The number of individuals with a specific genotype divided by the total number of individuals in the population.

Gene Pool

The complete set of genetic information within a population.

Heterozygous

An individual that has two different alleles at a specific locus.

Homozygous

An individual that has two identical alleles at a specific locus.

Hardy-Weinberg Principle

Model predicting allele and genotype frequencies in a population under certain conditions.

Hardy-Weinberg Equation

p² + 2pq + q² = 1, where p and q are allele frequencies.

Random Mating

Mating that occurs without regard to genotype or phenotype.

Statistical Analysis

The process of collecting and analyzing data to understand patterns or relationships.

DNA Profile

A unique set of genetic markers used to identify individuals.

Frequentist Approach

Statistical methods that treat probabilities as objective properties of the system studied.

Bayesian Probability

A method of statistics in which probabilities are based on prior knowledge or belief.

Conditional Probability

The probability of an event given another event has occurred.

Likelihood Ratio (LR)

A ratio comparing the probability of evidence under two different hypotheses.

Random Match Probability (RMP)

The probability that a match between two DNA profiles occurs by chance.

Probability of Exclusion (PE)

The likelihood that a certain genotype is not present in a mixed profile.

CODIS Software

A tool used to analyze DNA profiles and compare them to a database.

Eigenvalues

Values that indicate the stability of genetic frequencies in population genetics.

Sexual Selection

A type of natural selection driven by the mating preferences of individuals.

Genetic Drift

Random fluctuations in allele frequencies in a population.

Gene Migration

The transfer of genetic material between populations.

Mutation

A change in the DNA sequence that can introduce new alleles.

Stochastic Effects

Random variations that can affect allele frequencies.

Continuous Model

A statistical model that considers all alleles present in a mixture.

Probabilistic Genotyping

A method that uses statistical models to interpret complex DNA profiles.

Marker Chain Monte Carlo (MCMC)

A statistical method used in continuously modeling allele frequencies.

Error Rate

The percentage of measurements that deviate from the true value due to inaccuracies.

Uncertainty of Measurement

The doubt that exists about the result of any measurement.

Calibration

The process of adjusting an instrument to ensure accurate measurements.

Confidence Interval

A range of values that is likely to contain the true population parameter.

Systematic Error

An error that occurs due to a flawed measurement system.

Random Error

Unpredictable variations that can occur in any measurement.

Population Database

A collection of DNA profiles used for comparison in forensic investigations.

Short Tandem Repeat (STR)

Repeating sequences of DNA used in forensics for genetic profiling.

Quantitative Peak Height

Measurement of the amount of DNA present in a sample based on the height of DNA peaks in an analysis.

Biometrics

The statistical analysis of biological data for identifying individuals.

Mixed Profile

A DNA profile that contains contributions from multiple individuals.

Principal Component Analysis (PCA)

A statistical method used for reducing the dimensionality of data.

Variance

A statistical measure of the dispersion of a set of values.

Population Proportion

The fraction of the population exhibiting a particular genotype.

Microsatellite

Repeating sequences of DNA used for genetic profiling.

Evidence Weight

The significance of evidence in supporting a particular hypothesis in forensic science.

Statistical Significance

A measure of whether an observed effect or relationship is likely to be genuine or occurred by chance.

Power of a Test

The probability of correctly rejecting the null hypothesis.

Cohort

A group of individuals sharing a common characteristic studied over time.

Polymorphism

The occurrence of two or more different alleles at a locus in a population.

Genetic Marker

A specific sequence of DNA used to identify a particular location in the genome.

Allelic Dropout

The phenomenon where one allele is not detected in a genotype but is present.

Allelic Drop-in

The introduction of an extra allele not present in the original sample.

Biological Modeling

The application of mathematical models to the biology of populations.

Molecular Weight

The mass of a molecule, usually expressed in daltons.

Data Normalization

The process of adjusting values measured on different scales to a notionally common scale.

Null Hypothesis

A statement of no effect or no difference that is tested against an alternative hypothesis.

Confounding Variables

External factors that can affect the outcome of an experiment or study.

Assessment Protocols

Standardized methods used to interpret and analyze data.

Standard Deviation

A measure of the amount of variation or dispersion in a set of values.