-ppt-
DESCRIPTION
TRANSCRIPT
WELCOME TO AN SC 221Introduction to Animal Genetics
Lecture 1
Introduction to Animal Genetics
Three Sections of the Course
Qualitative Genetics
Three Sections of the Course
• Modes of Inheritance -- predict progeny phenotypic distribution based on parental genotypes
Qualitative Genetics
Population Genetics
Three Sections of the Course
• Modes of Inheritance -- predict progeny phenotypic distribution based on parental genotypes
• Gene and genotypic frequencies -- predict direction and magnitude of changes in a population
Quantitative Genetics
Three Sections of the Course
• Assessing genetic merit -- describe traits with statistics to predict next record, genetic merit, response to selection
P = G + E
P = G + E
Phenotype: observed expression of a trait
P = G + E
Phenotype: observed expression of a trait
Genotype: composite of all genes that influence a trait
P = G + E
Phenotype: observed expression of a trait
Genotype: composite of all genes that influence a trait
Environment: all non-genetic factors that influence a trait
Types of Traits
Qualitative Quantitative
Types of Traits
Qualitative
• few loci
Quantitative
• many loci
Types of Traits
Qualitative
• few loci
• discrete phenotypes
Quantitative
• many loci
• measured phenotypes
Types of Traits
Qualitative
• few loci
• discrete phenotypes
• little or no effect of the environment
Quantitative
• many loci
• measured phenotypes
• environmental effect can be larger
PREDICT
OUTCOME
UNDERSTANDING GENETIC PRINCIPLES OF
INHERITANCE
What’s new in genetics?
What’s new in genetics?• gene mapping
• using maps to find genes
• sequenced human DNA
• gene therapy
• application to human well being and animal productivity/health
Horns
No Horns
Gene interactions:
Epistasis
Harlequin Double Merle