Quider, Audrey Almi Francis B. October 23, 2021
BS Psychology 3
RR = would cause Rheumatoid Arthritis in both sexes
rr = would prevent the disorder in both sexes
Genotypes
Phenotypes
Female
Male
RR
Rheumatoid Arthritis
Rheumatoid Arthritis
Rr
Rheumatoid Arthritis
None
rr
None
None
(RR) (rr) = Rr (Father’s Genotype) xRr (Mother’s Genotype)
R
r
R
RR
Rr
r
Rr
rr
RR: male and female both have Rheumatoid Arthritis
Rr: male have no Rheumatoid Arthritis if female with Rheumatoid Arthritis
rr: male and female both have no Rheumatoid Arthritis
Genotypic Ratio: 1:2:1 (1 RR : 2 Rr : 1 rr)
Phenotypic Ratio: 3:1 (3 with Rheumatoid Arthritis : 1 with no Rheumatoid Arthritis)
Dominant Trait: ¾ 一 ¾ x 100 = 75%
Recessive Trait: ¼ 一 ¼ x 100 = 25%
Conclusion:
Therefore, the odds that both their progeny are going to have Rheumatoid Arthritis is 75%,
while, the odds that both genders are going to have a normal lifestyle and free from the disease is
25%.
