PROBLEM SET 3 – TRANSMISSION GENETICS: NON-MENDELIAN GENETICS
(Multiple Alleles, Sex Linked, Sex Influenced and Sex Limited Inheritance)
NAME: Edzekiel David A. Llacuna DATE: February 28, 2021
SOLVE THE FOLLOWING PROBLEMS:
NOTE: Give the complete solutions for the problems by giving the complete components of
a PUNNETT SQUARE. (You have the option to solve mathematically)
1. A paternity case is filed by Ms. Padilla claiming Mr. Santos is the father of her child. She is
Type A1+. Her child is O-. Mr. Padilla is B+. Can Ms. Padilla win the case? Account for your
answer.
2. Nystagmus is a condition in humans characterized by involuntary rolling of the eyeballs. The
allele for this condition is incompletely dominant and sex X linked. Three phenotypes are
possible: normal, slight rolling and severe rolling. A woman who exhibits slight nystagmus
and a normal man are considering marriage and ask a geneticist what the chance is that their
children will be affected. What will he tell them?
3. A bald man who has brown eyes whose mother is non bald with blue eyes married a non-bald
blue eyed woman whose father is bald. What is the probability of them producing:
a. bald brown eyed sons
b. bald blue eyed sons
c. non bald brown eyed daughters
d. non bald blue eyed daughters
e. bald brown eyed children
4. A rabbit gave birth to 8 rabbits. Four are agouti, two chinchilla rabbits and two Himalayan
rabbits. Give all possible parental genotypes.
Answers:
1. Paternity case of Ms. Padilla claiming Mr. Santos is the father of her child
Ms. Padilla’s Blood Type: A1+
Mr. Santos Blood Type: B+ A1+ A1- O+ O-
Child’s Blood Type: O-
A1B++ A1B+-
BO++ BO+-
Trait: Blood Type B+
Type Type
Legend or key: Type A1: A1A1; A1A2; A1A3; A1O Type B+ Type B+
A1B+ A1B+
Type B: BB or BO
rH +: ++ or +- A1B+- A1B--
BO+- BO--
rH -: -- B-
Type Type
Type B+ Type B-
A1B+ A1B-
Parental Genotype: A1O+- x BO+-
Gametes or Genes: A1+ A1- O+ O- B+ B- O+ O- A1O++ A1O+- OO++ OO+-
O+
Genotypic Ratio: 1:2:1:1:2:1:1:2:1:1:2:1 Type A1+ Type A1+ Type O+ Type O+
Phenotypic Ratio: 3:1:3:1:3:1:3:1
A1O+- A1O-- OO+- OO--
There is a chance that Mr. Santos is the father of her O-
child Type A1+ Type A1- Type O+ Type O-
2. A woman with slight nystagmus and a normal man, chance that their children will be affected.
Woman with slight nystagmus: XNXn
Normal Man: XNY
XN Xn
Trait: Nystagmus
Legend or key: XN – Normal; Xn – with nystagmus
XN XN XN XN Xn
Parental Genotype: XNXn x XNY
Gametes or Genes: XN Xn XN Y
Genotypic Ratio: 1:1:1:1 Y XN Y XnY
Phenotypic Ratio: 1:1:1:1
1 or 25% normal male
1 or 25% normal female
1 or 25% with nystagmus (slight rolling) female
1 or 25%with nystagmus (severe rolling) male
3. The probability of a bald man who has brown eyes whose mother is non bald with blue eyes
married a non-bald blue eyed woman whose father is bald.
Husband: Bbrr
Wife: BbRR
Trait: Baldness and eye color Br br Br br
Legend or key:
Males: BB –bald; Bb – bald; bb –
non-bald BbRr BBRr BbRr
BBRr
Females: BB –bald; Bb – non-bald; Bald male Bald male Bald male
Bald male
bb – non-bald blue eyed blue eyed blue eyed
BR blue eyed
Non-Bald Bald female Non-Bald
Blue eyes – R; Brown eyes – r Bald female
female blue blue eyed female blue
blue eyed
eyed eyed
Parental Genotype: BbRrr x BbRR bbRr bbRr
BbRr BbRr
Gametes or Genes: Br br Br br Non-Bald Non-Bald
Bald male Bald male
BR bR BR bR male blue male blue
blue eyed blue eyed
bR eyed eyed
Non-Bald Non-Bald
Genotypic Ratio: Non-Bald Non-Bald
female blue female blue
female blue female blue
Males: 12:4 or 3:1 eyed eyed
eyed eyed
Females: 4:12 or 1:3
BbRr BbRr
BBRr BBRr
Phenotypic Ratio: Bald male Bald male
Males: 12:4 or 3(bald blue eyed):1 Bald male Bald male
blue eyed blue eyed
BR blue eyed blue eyed
(non-bald blue eyed)
Females: 4:12 or 1(bald blue Non-Bald Non-Bald
Bald female Bald female
eyed):3(non-bald blue eyed) female blue female blue
blue eyed blue eyed
eyed eyed
a. bald brown eyed sons – 0/16 or bbRr bbRr
BbRr BbRr
0%
Non-Bald Non-Bald
b. bald blue eyed sons – 12/16 or Bald male Bald male
male blue male blue
75% blue eyed blue eyed
bR eyed eyed
c. non bald brown eyed daughters –
0/16 or 0% Non-Bald Non-Bald
Non-Bald Non-Bald
d. non bald blue eyed daughters - female blue female blue
female blue female blue
12/16 or 75% eyed eyed
eyed eyed
e. bald brown eyed children – 0/16
or 0%
4. All possible parental phenotype from a rabbit that has an offspring of four are agouti, two
chinchilla rabbits and two Himalayan rabbits
4:2:2 or 2(Agouti):1(Chinchilla):1(Himalayan)
IA Ih
Trait: Color coats in Rabbits
Legend or key: Agouti Rabbit: IAIA; IAIch; IAIh; IAIa
Chinchilla Rabbit: lchIch; IchIh; IchIa IAIch IhIch
Himalayan Rabbit: IhIh; IhIa I ch
Agouti Chinchilla
Ah ch h
Parental Genotype: I I x I I
Gametes or Genes: IA Ih Ich Ih I AI h IhIh
Ih
Genotypic Ratio: 1:1:1:1 Agouti Himalayan
Phenotypic Ratio: 2(Agouti):1(Chinchilla):1(Himalayan)
Legend or key: Agouti Rabbit: IAIA; IAIch; IAIh; IAIa Ich Ia
Chinchilla Rabbit: lchIch; IchIh; IchIa
Himalayan Rabbit: IhIh; IhIa
IAIch I AI a
Ah ch a
Parental Genotype: I I x I I IA
Gametes or Genes: IA Ih Ich Ia Agouti Agouti
Genotypic Ratio: 1:1:1:1 IchIh IhIa
Phenotypic Ratio: 2(Agouti):1(Chinchilla):1(Himalayan) I h
Chinchilla Himalayan
Legend or key: Agouti Rabbit: IAIA; IAIch; IAIh; IAIa
Chinchilla Rabbit: lchIch; IchIh; IchIa
Himalayan Rabbit: IhIh; IhIa
Ich Ia
ch a Ah
Parental Genotype: I I x I I
Gametes or Genes: Ich Ia IA Ih
I AI h I AI a
Genotypic Ratio: 1:1:1:1 IA
Phenotypic Ratio: 2(Agouti):1(Chinchilla):1(Himalayan) Agouti Agouti
Possible parental phenotype: IchIh IhIa
IAIh (Agouti Rabbit) x IchIh(Chinchilla Rabbit) I h
IAIh(Agouti Rabbit) x IchIa(Chinchilla Rabbit) Chinchilla Himalayan
IchIa(Chinchilla Rabbit) x IAIh(Agouti Rabbit)
