history of the munchkin first noted in 1940’s during london blitz cat reappears in stalingrad in...
TRANSCRIPT
History of the Munchkin
• First noted in 1940’s during London Blitz
• Cat reappears in Stalingrad in 1953
• Pregnant cat found in
Rayville LA in 1983
Munchkin Genetics
• Short bone structure in legs caused by a dominant allele
• What is the risk of breeding munchkin cats of unknown genotype?
How Is Heterozygosity A Problem In The Domestication of Animals?
Puggles & Labradoodles
Dihybridization• The probability of inheriting two traits
may be determined using a 16 box Punnett square.
• Each parent makes 4 possible gamete combinations from the two homologous pairs associated with the traits
• As before, gametes must contain only one chromosome from each homologous pair
• Homologous pairs are reunited in the 16 possible zygotes
Independent Assortment and Formation of Gametes
Phenotypic Ratios
• Phenotypic:
• Dom1Dom2: Dom1Rec2: Rec1Dom2: Rec1Rec2
Genotypic Outcomes
Sample Dihybridization
• Assume that the trait of smooth peas is dominant (S) relative to the trait of wrinkled peas (s)
• Assume that the trait of yellow peas (Y) is dominant to the trait of green (y)
• What proportion of the offspring from the cross of two true dihybrid parents (heterozygous for both traits) will belong to each of the four phenotypic categories?