Genetics
EXTENTION OF MENDELIAN INHERITANCE
Objective
The objectives of this experiment were to observe Mendel’s law with inheritance trait of the curly wing mutation and the interactions between the mutant genes of vestigial wings and curved wings in Drosophila.
Results
Part A
Cross A (wildtype females X curly males)
Male
Female
Wild type
1
2
Curly wing
0
1
Table 1. The number of the phenotypes and sex of offspring of the Cross A
Cross B (curly females X curly males)
Male
Female
Wild type
2
1
Curly wing
3
0
Table 2. The number of the phenotypes and sex of offspring of the Cross A
2. The cross A and B look like sex-linked traits, but it is not sex-linked dominant curly wing mutation and sex-linked recessive curly wing mutation. Thus, the curly wing genes have to be on an autosomal chromosome because the cross A showed wild type female reveals the sex-linked recessive, and the cross A had wild type females reveals the x-linked dominant at the same time in part A.
3.
Parent
P1
P2
Genotype
aa
Aa
Phenotype
Wild
Curly wing
*Wild type allele: a
*Curly wing allele: A Punnet Square
Cross A
P1
P2 a a
A
Aa
Aa
a aa aa
F1 Genotype aa Aa
F1 phenotype
Wild type
Mutant
Phenotype ratio
1
1
Cross B (P2 and P2)
P2
P2
A
A
A
Aa
Aa
A
Aa
A A
F1 Genotype
Aa
Aa
AA
F1 Phenogype
Wild type
Mutant
Lethal
Phenotype ratio
1
2
0
Theoretically, the proportion of the offspring from Cross A should be 1:1, and the proportion of the offspring from Cross B should be 1:2.
4.
Observed
Expected
O - E
(O – E)2
(O –E)2/E
A A
Lethal
0
0
0
0
A a
3
4
-1
1
0.25
a a
3
2
1
1
0.5
Total
6
6
0.75, p value is between 0.5 and 0.7. Thus, the difference between observation and expectation can be accepted.
Part B
F2
Wild Type
Veinlet
Vestigial
Veinlet/Vestigial
G11
1 Female/1 Male
1 Male
-
-
G12
1 Male
1 Female
1 Female
-
G13
1 Female / 1 Male
1 Female
-
-
G14
-
Objective
The objectives of this experiment were to observe Mendel’s law with inheritance trait of the curly wing mutation and the interactions between the mutant genes of vestigial wings and curved wings in Drosophila.
Results
Part A
Cross A (wildtype females X curly males)
Male
Female
Wild type
1
2
Curly wing
0
1
Table 1. The number of the phenotypes and sex of offspring of the Cross A
Cross B (curly females X curly males)
Male
Female
Wild type
2
1
Curly wing
3
0
Table 2. The number of the phenotypes and sex of offspring of the Cross A
2. The cross A and B look like sex-linked traits, but it is not sex-linked dominant curly wing mutation and sex-linked recessive curly wing mutation. Thus, the curly wing genes have to be on an autosomal chromosome because the cross A showed wild type female reveals the sex-linked recessive, and the cross A had wild type females reveals the x-linked dominant at the same time in part A.
3.
Parent
P1
P2
Genotype
aa
Aa
Phenotype
Wild
Curly wing
*Wild type allele: a
*Curly wing allele: A Punnet Square
Cross A
P1
P2 a a
A
Aa
Aa
a aa aa
F1 Genotype aa Aa
F1 phenotype
Wild type
Mutant
Phenotype ratio
1
1
Cross B (P2 and P2)
P2
P2
A
A
A
Aa
Aa
A
Aa
A A
F1 Genotype
Aa
Aa
AA
F1 Phenogype
Wild type
Mutant
Lethal
Phenotype ratio
1
2
0
Theoretically, the proportion of the offspring from Cross A should be 1:1, and the proportion of the offspring from Cross B should be 1:2.
4.
Observed
Expected
O - E
(O – E)2
(O –E)2/E
A A
Lethal
0
0
0
0
A a
3
4
-1
1
0.25
a a
3
2
1
1
0.5
Total
6
6
0.75, p value is between 0.5 and 0.7. Thus, the difference between observation and expectation can be accepted.
Part B
F2
Wild Type
Veinlet
Vestigial
Veinlet/Vestigial
G11
1 Female/1 Male
1 Male
-
-
G12
1 Male
1 Female
1 Female
-
G13
1 Female / 1 Male
1 Female
-
-
G14
-