Non-Mendelian Genetics

 Now that  you have a good grasp of

• how to calculate probabilities
• the vocabulary of genetics (genotype, phenotype, alleles, heterozygous, homozygous, dominant, recessive)
• using punnet squares to figure out the genotype and phenotype of offspring 

We are going to look at some patterns of inheritance that don't follow the simple dominant/recessive rules.

1. Read this explanation from the Kahn Academy about incomplete dominance, codominance, multigene traits.

2. Read this explanation from the Libre Text Biology  about sex linkage.

3. X–linked traits in mammals are carried on the X–chromosome. The proper symbols are the same as for any other gene, but as a superscript on the X–chromosome.

• Example: Hemophilia is a recessive, X–linked gene
• Female carrier = X^HX^h
• Female with Hemophilia = X^hX^h
• Normal male = X^HY
• Male with Hemophilia = X^hY