non-mend genetics notes is way of show.ppt

Non mendelian genetica

1. Non-Mendelian Non-Mendelian
GeneticsGenetics
Aim: What are some other ways Aim: What are some other ways
traits are shown?traits are shown?

2. Incomplete DominanceIncomplete Dominance
A.A.Both alleles Both alleles contribute to the contribute to the
phenotypephenotype of a heterozygous of a heterozygous
individual to produce a individual to produce a blending blending
(mixture) (mixture) of of either dominant geneeither dominant gene..
Example: cross between a Example: cross between a redred flower & a flower & a
whitewhite flower = flower = pinkpink flower flower..

3. Incomplete DominanceIncomplete Dominance
B.B.In incomplete dominance, In incomplete dominance, use capital use capital
letterletter for for both traits both traits since they both since they both
influence outcomeinfluence outcome..
Offspring
are 100%
pink
R R
WRWRW
WRWRW

4. Incomplete Dominance
C.Crossing a hybrid
25% Red25% Red
50% Pink50% Pink
25% White25% White
R W
R RRRW
W RWWW

5. Co-DominanceCo-Dominance
A.A.Two dominant alleles Two dominant alleles are expressed are expressed
at the at the same timesame time..
1. Results in 1. Results in simultaneous expression simultaneous expression of of
both alleles in the both alleles in the phenotypephenotype of a of a
heterozygousheterozygous individual. individual.
Example: Example: RoanRoan cattle w/mixture of cattle w/mixture of red & red &
white hairswhite hairs; human blood type.; human blood type.

7. Co-DominanceCo-Dominance
B.B.Co-dominance is written with capital Co-dominance is written with capital
letters & superscripts.letters & superscripts.
CC
RR
= = RedRed
CC
WW
= = WhiteWhite
CC
RR
CC
WW
= = RoanRoan
CC
RR
CC
RR
CC
WW
CC
RR
CC
WW
CC
RR
CC
WW
CC
WW
CC
RR
CC
WW
CC
RR
CC
WW

8. Multiple AllelesMultiple Alleles
A.A.There may be There may be more than 2 alleles more than 2 alleles for for
a trait in a species.a trait in a species.
1. Individuals cannot have more than 1. Individuals cannot have more than 2 2
alleles alleles for for each traiteach trait..
Example: Blood type Example: Blood type A, B, AB, OA, B, AB, O

9. Sex DeterminationSex Determination
A.A.Sex is genetically determined at Sex is genetically determined at
fertilizationfertilization when a sperm cell when a sperm cell
containing an containing an X or YX or Y chromosome chromosome
unites w/ an egg cell containing an unites w/ an egg cell containing an XX
chromosome.chromosome.
1. XX: produces 1. XX: produces femalefemale
2. XY: produces 2. XY: produces malemale

10. Sex-Linked TraitsSex-Linked Traits
A.A.Genes for Genes for certain traitscertain traits are located on are located on
the the X chromosomeX chromosome..
1. These genes 1. These genes do notdo not have a have a
corresponding allele corresponding allele on the Y chromosome.on the Y chromosome.
2. Many of these genes are 2. Many of these genes are recessiverecessive
therefore they are expressed more in therefore they are expressed more in malesmales
than than femalesfemales..
Example: Example: Hemophilia; colorblindnessHemophilia; colorblindness
3. Females are often 3. Females are often carrierscarriers..

11. The
Inheritance of
Hemophilia

12. Sex-Linked TraitsSex-Linked Traits
4.4.Pedigree charts Pedigree charts are used to show the are used to show the
presence or absencepresence or absence of particular of particular
inherited traitsinherited traits in humans. in humans.