Mendelian Genetics

Topics

Reminders

• Sept 1 and Sept 6, 1995
• Campbell Chp 13, pp 221-237
• Emphasis: class outline
• Study questions pp 238-239
• Examine study outline on pp 237-238

1. Introduction

• Inheritance as blending of traits
  "Bucket of paint"
• Particulate model of inheritance - gene (Mendel)
  "Bucket of marbles'

2. Mendel's Model: A Case Study in the Scientific Process

• Mendel's Experimental Approach
• Mendel's Law of Segregation
• Inheritance as a Game of Chance
• Mendel's Law of Independent Assortment

2.a Mendel's Experimental Approach

• Characters and traits
• Pea plants, all or none traits
• true breeding
• heritable factors (genes)
• hybridization
• monohybrid
• dihybrid
• parental generation P
• F1 generation
• F2 generation
• genotypes and phenotypes

2.b Mendel's Law of Segregation

• Alleles
• Two genes, one from each parent
• Dominant and recessive alleles
• Homozygous and heterozygous

2.c Inheritance as a Game of Chance

• The rule of multiplication
• The rule of addition
• The statistical nature of Inheritance

2.d Mendel's Law of Independent Assortment

• Hybrid
• Dihybrid cross

3. Extending Mendelian Genetics

• Incomplete dominance
• Multiple alleles
• Pleiotropy
• Epistasis
• Polygenic inheritance
• Nature versus nurture
• Integrating a Mendelian view of heredity and variation

4. Mendelian Inheritance in Humans

• Human pedigrees
• Recessively inherited disorders
• Dominantly inherited disorders
• Genetic screening and counseling