Information Package / Course Catalogue
Variance Components and Genetic Parameter Estimation
Course Code: ZZO529
Course Type: Area Elective
Couse Group: Second Cycle (Master's Degree)
Education Language: Turkish
Work Placement: N/A
Theory: 2
Prt.: 2
Credit: 3
Lab: 0
ECTS: 6
Objectives of the Course

The primary objective of this course is to provide graduate students in Animal Science with a comprehensive understanding of the theoretical foundations and practical applications of variance component estimation and genetic parameter analysis in animal breeding. The course aims to equip students with the knowledge required to quantify the genetic and environmental sources of phenotypic variation and to estimate key genetic parameters, including heritability, repeatability, genetic correlations, and phenotypic correlations, using performance, pedigree, and, where appropriate, genomic data. The course further develops students' competence in the application of modern quantitative genetic methodologies, including linear mixed models, Best Linear Unbiased Prediction (BLUP), and Restricted Maximum Likelihood (REML), for the estimation of breeding values and genetic parameters. Emphasis is placed on the interpretation of variance components, the evaluation of genetic merit, and the design of scientifically sound selection and breeding programs for livestock populations. Upon successful completion of the course, students will be able to critically evaluate quantitative genetic studies, select appropriate statistical models for different breeding scenarios, interpret the biological significance of estimated genetic parameters, and apply these concepts to support evidence-based genetic improvement programs in animal production systems.

Course Content

1- Definition and partitioning of variance components in quantitative genetics. 2- Data sources for genetic parameter estimation, including phenotypic, pedigree, and genomic information. 3- Experimental and breeding designs for estimating genetic parameters. 4- Genetic and phenotypic parameters in animal breeding: heritability, repeatability, genetic, phenotypic, and environmental correlations. 5- Principles, interpretation, and applications of genetic parameter estimation in animal breeding and selection programs. 6- Linear statistical models used in quantitative genetics, including fixed, random, and mixed models. 7- Properties of variance component estimators, including unbiasedness, consistency, efficiency, and precision. 8- Methods for variance component estimation, including ANOVA-based approaches, Maximum Likelihood (ML), Restricted Maximum Likelihood (REML), and Bayesian methods. 9- Best Linear Unbiased Prediction (BLUP) and breeding value estimation using variance components. 10- Computer software and practical applications for genetic evaluation and variance component estimation (e.g., BLUPF90, ASReml, WOMBAT, MTDFREML, DMU, and R).

Name of Lecturer(s)
Learning Outcomes
1.Define variance components and fundamental genetic parameters in quantitative genetics, explain their biological significance, and evaluate their importance in animal breeding.
2.Select appropriate experimental designs and statistical models for genetic parameter estimation using phenotypic, pedigree, and genomic data.
3.Estimate variance components and genetic parameters using ANOVA, Maximum Likelihood (ML), Restricted Maximum Likelihood (REML), and related methods, and interpret the results.
4.Apply modern quantitative genetic approaches, including BLUP and the Animal Model, to estimate breeding values and critically evaluate selection decisions.
5.Perform genetic evaluation analyses using software such as BLUPF90, ASReml, WOMBAT, MTDFREML,BUGA and R, and effectively communicate and apply the results in scientific studies and animal breeding programs.
Recommended or Required Reading
Weekly Detailed Course Contents
Week 1 - Theoretical & Practice
Introduction to quantitative genetics, definition of variance components, and partitioning of phenotypic variance
Week 2 - Theoretical & Practice
Data sources for genetic parameter estimation: phenotypic records, pedigree, and genomic information
Week 3 - Theoretical & Practice
Experimental and breeding designs for genetic parameter estimation
Week 4 - Theoretical & Practice
Heritability: definition, biological interpretation, and estimation methods
Week 5 - Theoretical & Practice
Estimation and interpretation of repeatability, genetic, phenotypic, and environmental correlations
Week 6 - Theoretical & Practice
Applications of genetic parameter estimation in animal breeding and selection programs
Week 7 - Theoretical & Practice
Linear statistical models in quantitative genetics: fixed, random, and mixed models
Week 8 - Theoretical & Practice
Properties of variance component estimators: unbiasedness, consistency, efficiency, and precision
Week 9 - Theoretical & Practice
ANOVA-based and Maximum Likelihood (ML) methods for variance component estimation
Week 10 - Theoretical & Practice
Restricted Maximum Likelihood (REML): theory and applications
Week 11 - Theoretical & Practice
Best Linear Unbiased Prediction (BLUP), the Animal Model, and breeding value estimation
Week 12 - Theoretical & Practice
Computer software for genetic evaluation: BLUPF90, ASReml, WOMBAT, MTDFREML,BUGA, and R
Week 13 - Theoretical & Practice
Practical data analysis for variance component and genetic parameter estimation, and interpretation of results
Week 14 - Theoretical & Practice
Critical evaluation of recent research, case studies, and overall course review
Assessment Methods and Criteria
Type of AssessmentCountPercent
Assignment1%10
Quiz1%10
Assignment Examination1%10
Final Examination1%70
Workload Calculation
ActivitiesCountPreparationTimeTotal Work Load (hours)
Lecture - Theory141242
Lecture - Practice141242
Assignment18311
Assignment Examination18311
Quiz18311
Final Examination130232
TOTAL WORKLOAD (hours)149
Contribution of Learning Outcomes to Programme Outcomes
PÇ-1
PÇ-2
PÇ-3
PÇ-4
PÇ-5
PÇ-6
PÇ-7
OÇ-1
5
5
5
3
3
2
5
OÇ-2
5
5
5
3
3
2
5
OÇ-3
5
5
5
3
3
2
5
OÇ-4
5
5
5
5
3
2
5
OÇ-5
4
3
4
3
3
2
4
Adnan Menderes University - Information Package / Course Catalogue
2026