Cootie Genetics

Cootie from the East Cootie from the West

Red R Blue r

Wide Ear W Bow w

Purple eye P Lashes p

Lips L Tongue l

Boots B Feet b

Cootie Traits

What does it all mean

• Trend—30:10 ratio of traits from the east versus traits from the west—or 3:1 ratio of dominant to recessive phenotypes

• Trend—10:10:10:10 ratio of trait factors RR, Rr, rR, rr—or 1:1:1:1 ratio. • Rr and rR are the same thing– 1:2:1

ratio of Homozygous dominant (RR) to Heterozygous (rR & rR) to Homozygous recessive (rr) genotypes

Punnett Square for the Homozygous Cooties—first

generation matingR

r

Cootie from the East

Cootiefrom the west

R

RR

R R

r r

rrr

Punnett Square for the Heterozygous Cooties—second

generation matingR

r

First Generation Offspring

First

Gen

erat

ion

Offsp

ring

R RR r

r

r

R

r R r