1. Mutation II

2. Mutation --- Chromosomal Level
??? Crossing over
Deletions (deficiencies)
Terminal
Intercalary
IF small, MIGHT not have a major effect.
Cri-du-chat Syndrome (cat cry syndrome) deletion in short arm of chromosome 5

3. Duplications Section present two or more times in a chromosome
If small might not have a negative effect.
Large duplication usually has a negative effect. WHY????
Evolutionary significance of duplicated material

5. Translocations Between non-homologous chromosomes
Reciprocal
Non-reciprocal
We will “assume” no position effect
In translocation heterozygotes fertility is reduced
Fertility (F) = 1 / 2n-1
n = number of chromosome pairs repatterned through translocation

6. Translocations Fertility reduction only happens in the heterozygotes!
Gives rise to cross and ring configurations during meiosis
Evolutionary importance --- partial isolation (reduced fertility in offspring of matings between different strains)
Our Example: a reciprocal translocation