For the pedigree given above which shows the inheritance of an autosomal recessive disorder, what is the genotype of the individual II - 3 ?
1. AA 2. Aa
3. aa 4. Cannot be determined
Subtopic:  Pedigree Analysis: More Examples |
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Level 2: 60%+
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Consider the inheritance of the trait as shown in the pedigree given above:
Assertion(A): The mode of inheritance cannot be X linked recessive.
Reason(R): The father of the affected female does not have the disease.
 
1. (A) is true, (R) is true, (R) explains (A)
2. (A) is true, (R) is true, (R) does not explain (A)
3. (A) is true, (R) is false
4. (A) is false, (R) is true

 
Subtopic:  Pedigree Analysis: Problem Solving |
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Level 3: 35%-60%
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Regarding the features of autosomal recessive inheritance
Statement(A): Affected individuals never appear among the offspring of unaffected parents
Statement(B): Affected offspring include only males
 
1. (A) is correct, (B) is correct 
2. (A) is correct, (B) is incorrect
3. (A) is incorrect, (B) is correct
4. (A) is incorrect, (B) is incorrect
Subtopic:  Pedigree Analysis: Basics | Mendelian Disorders |
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Level 2: 60%+
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A father affected with an X-linked recessive disorder will have no affected children; all daughters will be carriers. This conclusion is valid only if:
1. The mother is homozygous normal \((X^AX^A)\)
2. The mother is phenotypically normal (carrier status unknown).
 
Subtopic:  Pedigree Analysis: Problem Solving | Mendelian Disorders |
Level 4: Below 35%
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A female with normal vision has a colour blind son who also has haemophilia.
The female's father did not have haemophilia or colour blindness.
Considering both colour blindness and haemophilia are X-linked recessive traits, what is the genotype of the female?
1. \(X^{BH}X^{BH}\)
2. \(X^{BH}X^{bh}\)
3. \(X^{bh}X^{bh}\)
4. \(X^{Bh}X^{bH}\)
 
Subtopic:  Mendelian Disorders |
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Level 2: 60%+
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During genetic crosses, which recombination frequency value indicates that two genes assort independently and show no linkage?
1. 0 
2. 0.25 
3. 0.5
4. 0.75
Subtopic:  Linkage Types | Recombination & Gene Mapping |
Level 4: Below 35%
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