Genetic analysisDonald Winslow

25 February 2011

Green peas from Donald’s garden

Gregor Mendel

Illustration from Chapter 3 (Mendelian Genetics) of Klug et al., 2009Concepts of Genetics, 9th ed. Pearson/Benjamin Cummings, San Francisco.

Objectives Define: heterozygous, homozygous, recessive,

dominant, codominant, incomplete dominance, Punnett square, monohybrid cross, dihybrid cross, phenotype, genotype,

P generation, F1 generation, F

2 generation

Explain segregation & independent assortment Use Punnett squares to predict results of

monohybrid & dihybrid crosses Including human blood group crosses

Monohybrid cross

Illustration from Chapter 3 (Mendelian Genetics) of Klug et al., 2009Concepts of Genetics, 9th ed. Pearson/Benjamin Cummings, San Francisco.

Segregation observedParental (P) Generation: Yellow peas X Green peas

First Filial (F1) Generation: Yellow peas

Second Filial (F2) Generation: Yellow peas + Green peas

Dihybrid cross

Illustration from Chapter 3 (Mendelian Genetics) of Klug et al., 2009Concepts of Genetics, 9th ed. Pearson/Benjamin Cummings, San Francisco.

Autosomal & sex-linked genes

Autosomes have homologues Sex linkage

Sex determination in Drosophila & humans Heterogametic and homogametic sex

Pedigree analysis

Male squares, female circles Autosomal recessive disorders Autosomal dominant disorders X-linked recessive disorders Polymorphism—PTC tasting