Genetics & Evolution for the MCAT

Mendelian Genetics

• Segregation: Alleles separate in meiosis
• Independent Assortment: Genes on different chromosomes sort independently
• Punnett squares: Aa × Aa → 3:1 phenotype ratio

Non-Mendelian Patterns

• Incomplete dominance (intermediate phenotype)
• Codominance (both expressed, e.g., AB blood type)
• X-linked inheritance (males hemizygous)
• Polygenic traits (continuous distribution)

Population Genetics

$p^2 + 2pq + q^2 = 1 \quad \text{(Hardy-Weinberg)}$