Unit 2 Learning Objectives

Determine the appropriate null hypothesis for a chi-square test, calculate the chi-square statistic, and interpret the statistical significance of the result

Calculate allele frequencies from genotype or phenotype frequencies; calculate genotype or phenotype frequencies from allele frequencies

Apply the 𝜒2 test to determine whether a cross or a population deviates from our expectations under a null genetic model. Explain what are the potential causes of deviation from these expectations

Use the Hardy-Weinberg formula that relates allele and genotype frequencies to
demonstrate why disease alleles are most commonly found in heterozygote carriers.

Use the ABO blood-type locus to examine genetic variation at alleles at a locus that have codominant effects and to extend the HWE to a locus with more than 2 alleles. What is the evidence
that balancing selection maintains variation at this locus and the hemoglobin locus?

Predict the outcome of selection based on the patterns of relative fitness among genotypes. How do patterns of dominance affect this? Why do you think it may be hard to predict the outcome
of evolution?

Write sentences that correctly use the terms inheritance, alleles, genes, phenotypes, fitness and selection.

Use biochemical pathways to describe how alleles at a locus interact to affect a phenotype and how alleles at two genes can interact to affect a single phenotype.

Apply the logic of a di- or trihybrid cross to predict the expected frequencies of multi-trait states when loci assort independently.

Use an allelic series to distinguish between mutant and wild type alleles and to demonstrate how allele with different types of dominance affect phenotypes.

Place the terms dominance, pleiotropy and epistasis on
our model of how alleles and genes affect phenotypes.

Use a complementation test to determine whether two mutations are alleles of the same or different genes

Follow the inheritance of traits using familial pedigrees to demonstrate why autosomal and X-linked traits have different patterns of inheritance.

Expand your mono- and di-hybrid cross logic to incorporate inheritance of alleles at an X-linked locus.

Use genetic models to show how the combined action of alleles at
multiple loci following Mendelian principles can produce a quantitative trait. And, contrast quantitative traits with categorical traits.

Draw a graph that exemplifies how the effects of alleles at a locus
can depend on the environment.

Use the Calico study on human longevity to explain to a friend why estimating trait heritability for human traits is very challenging

Apply your knowledge of heritability to make predictions about how traits will respond to selection. How is this related to our domesticated and agricultural species?

Draw the products of recombination resulting from crossing over between linked genes. Contrast the outcomes with the outcomes of independent assortment. Use outcomes of crosses to determine the distance between linked genes.

Apply the laws of probability to estimate the expected frequency of double crossovers.

Use data from a three-point cross to order loci on a chromosome and estimate the extent of interference. How does interference modify our expectation for the number of double crossovers?