About the course

Course website

• Online HTML slides
• Important dates

Canvas

• Announcements
• Handouts
• homework assignments (keys)

Course format

• In-person lecture session (with the Zoom option if needed)
• In-class computational demo (Using R software for statistical computing)

Scope of the Course

Population genetics

Study the genetic composition of natural populations and its evolutionary causes and consequences.

• Popgen is the study of evolution.

• The language of popgen is Mathematics.

Quantitative genetics

Study of the genetic basis of phenotypic variation.

• Quantgen is the study of the complex trait, or phenotype.

• The language of Quantgen is Statistics.

• AGRO-932 (Biometrical genetics and plant breeding)

  • Spring of every even-numbered year (next offfer: Spring 2024)

Population genetics

• Gregor Mendel, the founder of modern genetics.

• Charles Darwin, the founder of modern evolution.

Population genetics emerged from early efforts to reconcile Mendelian genetics with Darwinian thought.

• Many of the important ideas and mathematical models emerged before the 1940s
• Before DNA was discovered and yet the usefulness of these models has not diminished

Quantitative genetics

It almost synonymous with statistics!

• R. A. Fisher is a founder of quantitative genetics but also of analysis of variance and randomization procedures in statistics.

• The early geneticist Karl Pearson originated the concepts of regression and correlation.

In the 2nd part of the course, we will be deeply involved with the statistical evaluation of the basic quantitative genetic models.

Texts and other readings

Falconer & Mackay, 1996 Introduction to Quantitative Genetics. Fourth Edition.

Study the material before class meets.

• Pay attention to the problems in the textbook.
• Note that problems and solutions are presented at the end of the text.

Definitions

Locus (plural: loci)

A locus is a specific spot in the genome: maybe an entire gene, or a single base pair.

• such as, chr1 from 1001-1005: A A T C G.

Alleles

At each genetic locus, there may be multiple genetic variants segregating in the population --- these are known as alleles.

• allele 1: A A T C G.
• allele 2: A A C C G.

Allele transfers from one generation to next

Genotype

• A Genotype is a pair of alleles Genotype is not transferred from one generation to the next due to segregation of alleles.

Population

A population is a group of interbreeding individuals

• Same species
• Close proximity
• Share a gene pool

• Each offspring = random sample of one egg and one sperm from the gene pool
• The probability of sampling a particular allele = the frequency of that allele in the gene pool, assuming equal fitness, random mating, ...