Paternity Testing

Goal of Paternity Testing

To determine whether a particular man is the biological father of a child.

In Trio

Refers to the analysis of genetic material from the mother, father, and child together during paternity testing.

Criteria for Selecting Genetic Systems

Six criteria include polymorphism, easy deductibility of genotype from phenotype, reliability, availability, high mutation rate, and population distribution.

Genotype

The genetic constitution of an individual; the specific alleles at a given locus.

Phenotype

The observable characteristics or traits of an individual that result from the interaction of genotype with the environment.

Genotype is easily deductible from phenotype

This means that one's genetic makeup can often be inferred from observable traits.

Polymorphism

The occurrence of two or more genetically determined forms in the same population; for example, blood type variations.

Importance of Polymorphism in Paternity Testing

Polymorphism provides variability within genetic markers, allowing for more accurate paternity testing.

Inclusion and Exclusion

In paternity testing, inclusion means that a tested individual could be the biological parent, while exclusion means they cannot be.

Mendelian's Theory of Inheritance

Describes how genes and traits are passed from parents to offspring; includes the concepts of dominance and segregation.

Codominance

A condition in which both alleles in a heterozygote are fully expressed, as seen in AB blood type.

Punnett Square

A diagram used to predict genetic outcomes of a crossing between two individuals.

Amorph Gene

A gene that does not produce a detectable product, often related to blood type.

Rh Inheritance Exception

The only exception in Rh antigens is the D antigen, which determines Rh positivity or negativity.

Duffy Genes Amorph Gene

The non-expressing allele of the Duffy blood group, which lacks the corresponding antigen.

HLA (Human Leukocyte Antigen)

HLA I and II are critical for immune response and are essential for compatibility in organ transplantation.

DNA Polymorphism: RFLP

Restriction Fragment Length Polymorphism, a technique used to differentiate between individuals' DNA.

Inclusionary Calculation

A process to determine the likelihood of paternity based on genetic markers.

Paternity Index Formula

A statistical measure that quantifies the likelihood of a man being the biological father.

Probability of Paternity

The likelihood that a particular man is the biological father, derived from genetic evidence.

Probability of Exclusion

The probability that a tested man is not the biological father of the child.

Direct Exclusion

When genetic analysis shows that a man cannot be the father of a child.

Indirect Exclusion

Suggests that a man is unlikely to be the father based on the genetic evidence.

False Indirect Exclusion

Occurs when a paternity test incorrectly suggests a man is not the father despite being the biological parent.

False Direct Exclusion

Occurs when a paternity test incorrectly excludes a biological father due to testing error.