Patterns of InheritanceChapter 10

Gregor Mendel

• Austrian Monk (1800’s)

• Mathematician

• Heritable factors

• Peas

Mendel’s Traits

Generations

Mendel’s 4 Theories

• Alternate forms of genes exist (Alleles)

• 2 genes per trait

• Gamete only carries one allele

• Dominance vs. Recessive

Testcross

Probability

Mendel Got Lucky

• Incomplete Dominance

• Multiple Alleles

• Pleiotropy

• Polygenic inheritance

• Linkage

Incomplete Dominance

RR Rr rr

Multiple Alleles

Pleiotropy

Polygenic Inheritance

Other Info• Chromosomes determine sex in many species,

not just humans

• Sex chromosomes carry other genes– Sex linked– Some diseases have sex linkage component