HMB265H1 Lecture Notes - Lecture 6: Dihybrid Cross, Wild Type, Epistasis

• School: UTSG
• Department: Human Biology
• Course: HMB265H1
• Professor: Maria Papaconstantinou

Document Summary

Hmb265: human and general genetics lecture #6. Wrinkles on mendel"s laws: gene interactions: complementation/allelism, epistasis. Reading: hartwell et al. , 1st can. edition, chapter 2 (emphasis on pages 42-51) and. Shows that there are many steps to making an eye; suggests that different subspecies have mutations in different steps or pathways. Different null mutations in the same gene should give rise to the same phenotype. Mutations in the same gene can give rise to the same phenotype but mutations in different genes might also give rise to the same phenotype. The wild-tyle allele complements the mutant alleles so that the phenotype is wild-type. It provides what the other allele is lacking = compensation. When mutant alleles at the same locus cannot complement each other: they are allelic. Two mutant alleles cannot complement each other so the phenotype is mutant indicator of allelism: when they don"t complement. Two mutant alleles cannot complement each other so the phenotype is mutant indicator of allelism.