Paternity Testing

I. Goal of Testing

  • What is the goal of paternity testing?

  • What is “In trio” meaning?

II. Criteria of Selecting Genetic System

  • What are the criterions (6)?

  • Explain genotype and phenotype

  • Explain this criterion “Genotype is easily deductible from phenotype”.

A. Polymorphism

  • What is polymorphism? Example.

  • Why does this matter in choosing genetic system?

  • Why is polymorphism important in paternity testing?

B. Mendelian’s Theory of Inheritance

  • What are the two theories of inheritance under this?

  • Explain the two.

III. Examples of Genetic System

  • Give examples of Genetic system we can use.

  • These genetic systems are commonly used nowadays in paternity testing and is more accurate.

  • Explain inclusion and exclusion.

A. RBC Antigens

  • What are the genetic systems we can use under RBC antigens? (Mnemonics)

  1. Punnet Square

  • What does Mendel’s theory say about genes inheritance of the child?

  • What can we predict using punnet square?

  • What is/are the genotype of the blood types (A, B, AB, O)

  • What is the amorph gene?

  • For example, if the father has blood type O and the

    mother is homozygous AA, using a Punnett square,

    we expect that all the offspring will have blood type?

  • If the child’s blood type is B, then the mother’s is A, what is the possible blood type of the father?

  • If the child’s blood type is AB, then the mother’s is B, what is the possible blood type of the father?

  1. Rh Inheritance

  • What is the only exception in Rh antigens that we can use for genetic marker for testing?

  • If the father is heterozygous for the D gene (Dd) and the

    mother has no D gene (dd), what is the percentage of

    offspring that will be Rh positive?

  1. Duffy Genes

  • Why does having the “codominant” property important in selecting genetic marker?

  • What is the amorph gene of Duffy gene?

  • Give the genotype of the following?

  • If this is the scenario Fy (a-b-), will you include or exclude

    the duffy antigens blood group?

    • Is the child related to the father?

  1. Kidd Genes

  • What Kidd genotype are common in Whites and Blacks?

  • What Kidd genotype are rare in both white and black?

B. HLA (Human Leukocyte Antigen)

  • HLA I and II are the most?

  • What does HLA do in organ transplantation?

C. DNA Polymorphism: RFLP

  • What does DNA Polymorphism: RFLP do?

  • What are the three types of RFLP?

  • What does endonucleus do and what are the sources?

  • Procedure:

    • Once the sample from the mother, father, and child is

      obtained, it will be _____ , then subjected to a

      _________, and eventually there will be an

      appearance of _____.

  • Interpret the result:

  • How do we report?

III. Inclusionary Calculation

  • What does inclusionary calculation do?

  • Paternity Index = ?

  • Probability of paternity = ?

  • Probability of Exclusion = ?

A. Paternity Index

  • Also known as the?

  • Explain the purpose of paternity index

  • Explain the variables in paternity index formula

  • What does RFLP or VNTR measure?

  • Interpret

B. Probability of Paternity

  • The probability of paternity is based on what theorem?

  • What is the purpose of probability of paternity?

  • What is the formula for probability of paternity?

  • Find the probability of paternity using the image below:

  • What is prior probability of paternity?

C. Probability of Exclusion

  • What is the purpose of this?

  • What is the formula?

  • Using the image below, compute for the probability of exclusion.

D. Result Interpretation

  • What is direct exclusion?

  • In blacks, what type of duffy gene is common?

  • What is indirect exclusion?

  • Direct or indirect exclusion?

  • Direct or indirect exclusion?

E. False Exclusions

  • Explain false indirect exclusion and false direct exclusion

  • Identify the direct exclusions and indirect exclusions?