Contents

1 Basic Genetics

1.1 Introduction

1.2 Genes and Chromosomes

1.3 Meiosis

1.4 Mendel's Laws

1.4.1 Mendel's First Law

1.4.2 Mendel's Second Law

1.5 Linkage and Mapping

1.6 Interference

1.7 Quantitative Genetics

1.7.1 Population Properties of Genes

1.7.2 A General Quantitative Genetic Model

1.7.3 Genetic Models for the Backcross and F2 Design

1.7.4 Epistatic Model

1.7.5 Heritability and Its Estimation

1.7.6 Genetic Architecture

1.7.7 The Estimation of Gene Number

1.8 Molecular Genetics

1.9 SNP

1.10 Exercises

1.11 Note

1.11.1 Modeling Unequal Genetic EŽects by the Gamma Function

1.11.2 Modeling Unequal Genetic EŽects by a Geometric Series


2 Basic Statistics

2.1 Introduction

2.1.1 Populations and Models

2.1.2 Samples

2.2 Likelihood Estimation

2.3 Hypothesis Testing

2.3.1 The Pearson Chi-Squared Test

2.3.2 Likelihood Ratio Tests

2.3.3 Simulation-Based Approach

2.3.4 Bayesian Estimation

2.4 Exercises


3 Linkage Analysis and Map Construction

3.1 Introduction

3.2 Experimental Design

3.3 Mendelian Segregation

3.3.1 Testing Marker Segregation Patterns

3.4 Segregation Patterns in a Full-Sib Family

3.5 Two-Point Analysis

3.5.1 Double Backcross

3.5.2 Double Intercross - F2

3.6 Three-Point Analysis

3.7 Multilocus Likelihood and Locus Ordering

3.8 Estimation with Many Loci

3.9 Mixture Likelihoods and Order Probabilities

3.10 Map Functions

3.10.1 Mather's Formula

3.10.2 The Morgan Map Function

3.10.3 The Haldane Map Function

3.10.4 The Kosambi Map Function

3.11 Exercises

3.12 Notes: Algorithms and Software for Map Construction


4 A General Model for Linkage Analysis in Controlled Crosses

4.1 Introduction

4.2 Fully Informative Markers: A Diplotype Model

4.2.1 Two-Point Analysis

4.2.2 A More General Formulation

4.2.3 Three-Point Analysis

4.2.4 A More General Formulation

4.3 Fully Informative Markers: A Genotype Model

4.3.1 Parental Diplotypes

4.4 Joint modeling of the Linkage, Parental Diplotype, and Gene Order

4.5 Partially Informative Markers

4.5.1 Joint modeling of the Linkage and Parental Diplotype

4.5.2 Joint modeling of the Linkage, Parental Diplotype, and Gene

Order

4.6 Exercises

4.6.1 One dominant marker

4.6.2 One dominant marker and one F2 codominant marker

4.7 Notes

4.7.1 Linkage Analysis

4.7.2 The Diplotype Probability

4.7.3 Gene Order

4.7.4 M-Point Analysis


5 Linkage Analysis with Recombinant Inbred Lines

5.1 Introduction

5.2 RILs by SelŻng

5.2.1 Two-Point Analysis

5.2.2 Three-Point Analysis

5.3 RILs by Sibling Mating

5.3.1 Two-point Analysis

5.3.2 Three-Point Analysis

5.4 Bias Reduction

5.4.1 RILs by Selfing

5.4.2 RILs by Sibling Mating

5.5 Multiway RILs

5.6 Exercises

5.7 Note


6 Linkage Analysis for Distorted and Misclassified Markers

6.1 Introduction

6.2 Gametic Differential Viability

6.2.1 One-Gene Model

6.2.2 Two-Gene Model

6.2.3 Simulation

6.3 Zygotic Differential Viability

6.3.1 One-Gene Model

6.3.2 Two-Gene Model

6.3.3 Simulation

6.4 Misclassification

6.4.1 One-gene Model

6.4.2 Two-Gene Model

6.5 Simulation

6.6 Exercises


7 Special Considerations in Linkage Analysis

7.1 Introduction

7.2 Linkage Analysis with a Complicated Pedigree

7.2.1 A Nuclear Family

7.2.2 Multipoint Estimation of Identical-By-Descent Sharing

7.2.3 A Complex Pedigree

7.3 Information Analysis of Dominant Markers

7.3.1 Introduction

7.3.2 Segregation Analysis

7.3.3 Linkage Analysis

7.4 Exercises


8 Marker Analysis of Phenotypes

8.1 Introduction

8.2 QTL Regression Model

8.3 Analysis at the Marker

8.3.1 Two-Sample t Test

8.3.2 Analysis of Variance

8.3.3 Genetic Analysis

8.4 Moving Away from the Marker

8.4.1 Likelihood

8.5 Power Calculation

8.6 Marker Interaction Analysis

8.6.1 ANOVA

8.6.2 Genetic Analysis

8.7 Whole-Genome Marker Analysis

8.8 Exercises


9 The Structure of QTL Mapping

9.1 Introduction

9.2 The Mixture Model

9.2.1 Formulation

9.2.2 Structure, Setting, and Estimation

9.3 Population Genetic Structure of the Mixture Model

9.3.1 Backcross/F2

9.3.2 Outbred Crosses

9.3.3 Recombinant Inbred Lines

9.3.4 Natural Populations

9.4 Quantitative Genetic Structure of the Mixture Model

9.4.1 Additive-Dominance Model

9.4.2 Additive-Dominance-Epistasis Model

9.4.3 Multiplicative-Epistatic Model

9.4.4 Mechanistic Model

9.5 Experimental Setting of the Mixture Model

9.6 Estimation in the Mixture Model

9.7 Computational Algorithms for the Mixture Model

9.7.1 EM Algorithm

9.7.2 Monte Carlo EM

9.7.3 Stochastic EM

9.7.4 An EM Algorithm/Newton-Raphson Hybrid

9.7.5 Some Cautions

9.7.6 Bayesian Methods

9.7.7 Estimating the Number of Components in a Mixture Model

9.8 Exercises


10 Interval Mapping with Regression Analysis

10.1 Introduction

10.2 Linear Regression Model

10.3 Interval Mapping in the Backcross

10.3.1 Conditional Probabilities

10.3.2 Conditional Regression Model

10.3.3 Estimation and Test

10.4 Interval Mapping in an F2

10.5 Remarks

10.6 Exercises


11 Interval Mapping by Maximum Likelihood Approach

11.1 Introduction

11.2 QTL Interval Mapping in a Backcross

11.2.1 The Likelihood

11.2.2 Maximizing the Likelihood

11.3 Hypothesis Testing

11.3.1 Model for Incorporating Double Recombination

11.3.2 Model for Incorporating Interference

11.4 QTL Interval Mapping in an F2

11.4.1 No Double Recombination

11.4.2 Independence

11.4.3 Interference

11.4.4 Testing Hypotheses

11.5 Factors That Affect QTL Detection

11.6 Procedures for QTL Mapping

11.6.1 The Number of QTLs

11.6.2 Locations of Individual QTLs

11.7 Exercises


12 Threshold and Precision Analysis

12.1 Introduction

12.2 Threshold Determination

12.2.1 Background

12.2.2 Analytical Approximations

12.2.3 Simulation Studies

12.2.4 Permutation Tests

12.2.5 A Quick Approach

12.2.6 A Score Statistic

12.3 Precision of Parameter Estimation

12.3.1 Asymptotic Variance-Covariance Matrix

12.3.2 Simulation Studies

12.4 Confidence Intervals for the QTL Location

12.5 Exercises


13 Composite QTL Mapping

13.1 Introduction

13.2 Composite Interval Mapping for a Backcross

13.2.1 The Likelihood

13.2.2 Maximizing the Likelihood

13.2.3 Hypothesis Testing

13.3 Composite Interval Mapping for an F2

13.4 A Statistical Justification of Composite Interval Mapping

13.4.1 Conditional Marker (Co)variances

13.4.2 Conditional QTL Variance

13.4.3 Marker Selection

13.5 Comparisons Between Composite Interval Mapping and Interval

Mapping

13.6 Multiple Interval Mapping

13.7 Exercises


14 QTL Mapping in Outbred Pedigrees

14.1 Introduction

14.2 A Fixed-Effect Model for a Full-Sib Family

14.2.1 Introduction

14.2.2 A Mixture Model for a Parental Diplotype

14.2.3 Quantitative Genetic Model

14.2.4 Likelihood Analysis

14.2.5 Fitting Marker Phenotypes

14.2.6 Hypothesis Tests

14.2.7 The Influence of Linkage Phases

14.3 Random-Effect Mapping Model for a Complicated Pedigree

14.3.1 Introduction

14.3.2 Statistical Model

14.3.3 IBD at a QTL

14.3.4 The Likelihood

14.3.5 Hypothesis Testing

14.4 Exercises


A General Statistical Results and Algorithms

A.1 Likelihood Asymptotics

A.2 General Form of the EM Algorithm


B R Programs

B.1 Chapter 2

B.2 Chapter 8


C References