tt
dwarf
gg
yellow
that 2 genes affecting different traits are heterozygous (segregating)
in all the f1 progeny.
individual, the progeny will show the expected 3 dominant : 1
recessive phenotypic ratio for each trait.
give a ratio based on 16ths::
9
3
3
1
T_, G_
T_, gg
tt, G_
tt, gg
Tall, Green
Tall, yellow
Dwarf, Green
Dwarf, Yellow
the outcome expected for each trait (3 Tall : 1 dwarf) (3Green : 1
cross is proof that the 2 traits are independent.
same chromosome, we can expect them to segregate in
an independent fashion. We will also see exceptions to
the expected 9:3:3:1 F2 dihybrid ratio if one or both
genes does not show a simple dominant/recessive
pattern of inheritance, or if both genes affect the same
phenotypic character.