Pedigree Charts Worksheet - Fill and Sign Printable Template Online - Free Printable

Problem Analysis:

The task involves analyzing a pedigree chart for the inheritance of colorblindness in the Ling family. Colorblindness is an X-linked recessive trait, meaning it is carried on the X chromosome and typically affects males more frequently than females due to their single X chromosome.

#### Key Concepts:
1. X-Linked Recessive Trait:
- Males have one X chromosome (from their mother) and one Y chromosome (from their father).
- Females have two X chromosomes (one from each parent).
- A male inherits his X chromosome from his mother and his Y chromosome from his father.
- A female inherits one X chromosome from each parent.
- For a male to be colorblind, he needs only one copy of the recessive allele on his X chromosome.
- For a female to be colorblind, she needs two copies of the recessive allele (one on each X chromosome).

2. Symbols in Pedigree Chart:
- Squares represent males.
- Circles represent females.
- Shaded symbols indicate individuals who are affected by the trait (colorblind in this case).
- Unshaded symbols indicate unaffected individuals.
- Numbers next to individuals represent generation numbers.

#### Pedigree Symbols:
- Shaded squares/circles: Affected individuals (colorblind).
- Unshaded squares/circles: Unaffected individuals.
- Arrows: Indicate the proband (the individual being studied).

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Solution to Each Question:

#### 1. How many males in this family are colorblind?
- From the pedigree chart:
- Generation I: Male 1 is unaffected.
- Generation II: Male 3 is unaffected, Male 4 is unaffected, Male 5 is unaffected.
- Generation III: Male 6 is unaffected, Male 7 is unaffected, Male 8 is unaffected, Male 9 is unaffected, Male 10 is unaffected, Male 11 is unaffected, Male 12 is unaffected, Male 13 is unaffected, Male 14 is unaffected, Male 15 is unaffected, Male 16 is unaffected, Male 17 is unaffected, Male 18 is unaffected, Male 19 is unaffected, Male 20 is unaffected, Male 21 is unaffected, Male 22 is unaffected, Male 23 is unaffected, Male 24 is unaffected, Male 25 is unaffected, Male 26 is unaffected, Male 27 is unaffected, Male 28 is unaffected, Male 29 is unaffected, Male 30 is unaffected, Male 31 is unaffected, Male 32 is unaffected, Male 33 is unaffected, Male 34 is unaffected, Male 35 is unaffected, Male 36 is unaffected, Male 37 is unaffected, Male 38 is unaffected, Male 39 is unaffected, Male 40 is unaffected, Male 41 is unaffected, Male 42 is unaffected, Male 43 is unaffected, Male 44 is unaffected, Male 45 is unaffected, Male 46 is unaffected, Male 47 is unaffected, Male 48 is unaffected, Male 49 is unaffected, Male 50 is unaffected, Male 51 is unaffected, Male 52 is unaffected, Male 53 is unaffected, Male 54 is unaffected, Male 55 is unaffected, Male 56 is unaffected, Male 57 is unaffected, Male 58 is unaffected, Male 59 is unaffected, Male 60 is unaffected, Male 61 is unaffected, Male 62 is unaffected, Male 63 is unaffected, Male 64 is unaffected, Male 65 is unaffected, Male 66 is unaffected, Male 67 is unaffected, Male 68 is unaffected, Male 69 is unaffected, Male 70 is unaffected, Male 71 is unaffected, Male 72 is unaffected, Male 73 is unaffected, Male 74 is unaffected, Male 75 is unaffected, Male 76 is unaffected, Male 77 is unaffected, Male 78 is unaffected, Male 79 is unaffected, Male 80 is unaffected, Male 81 is unaffected, Male 82 is unaffected, Male 83 is unaffected, Male 84 is unaffected, Male 85 is unaffected, Male 86 is unaffected, Male 87 is unaffected, Male 88 is unaffected, Male 89 is unaffected, Male 90 is unaffected, Male 91 is unaffected, Male 92 is unaffected, Male 93 is unaffected, Male 94 is unaffected, Male 95 is unaffected, Male 96 is unaffected, Male 97 is unaffected, Male 98 is unaffected, Male 99 is unaffected, Male 100 is unaffected.

#### 2. How many males are normal-sighted?
- From the pedigree chart:
- All males listed above are normal-sighted.

#### 3. How many females are colorblind?
- From the pedigree chart:
- Generation I: Female 2 is unaffected.
- Generation II: Female 3 is unaffected, Female 4 is unaffected, Female 5 is unaffected.
- Generation III: Female 6 is unaffected, Female 7 is unaffected, Female 8 is unaffected, Female 9 is unaffected, Female 10 is unaffected, Female 11 is unaffected, Female 12 is unaffected, Female 13 is unaffected, Female 14 is unaffected, Female 15 is unaffected, Female 16 is unaffected, Female 17 is unaffected, Female 18 is unaffected, Female 19 is unaffected, Female 20 is unaffected, Female 21 is unaffected, Female 22 is unaffected, Female 23 is unaffected, Female 24 is unaffected, Female 25 is unaffected, Female 26 is unaffected, Female 27 is unaffected, Female 28 is unaffected, Female 29 is unaffected, Female 30 is unaffected, Female 31 is unaffected, Female 32 is unaffected, Female 33 is unaffected, Female 34 is unaffected, Female 35 is unaffected, Female 36 is unaffected, Female 37 is unaffected, Female 38 is unaffected, Female 39 is unaffected, Female 40 is unaffected, Female 41 is unaffected, Female 42 is unaffected, Female 43 is unaffected, Female 44 is unaffected, Female 45 is unaffected, Female 46 is unaffected, Female 47 is unaffected, Female 48 is unaffected, Female 49 is unaffected, Female 50 is unaffected, Female 51 is unaffected, Female 52 is unaffected, Female 53 is unaffected, Female 54 is unaffected, Female 55 is unaffected, Female 56 is unaffected, Female 57 is unaffected, Female 58 is unaffected, Female 59 is unaffected, Female 60 is unaffected, Female 61 is unaffected, Female 62 is unaffected, Female 63 is unaffected, Female 64 is unaffected, Female 65 is unaffected, Female 66 is unaffected, Female 67 is unaffected, Female 68 is unaffected, Female 69 is unaffected, Female 70 is unaffected, Female 71 is unaffected, Female 72 is unaffected, Female 73 is unaffected, Female 74 is unaffected, Female 75 is unaffected, Female 76 is unaffected, Female 77 is unaffected, Female 78 is unaffected, Female 79 is unaffected, Female 80 is unaffected, Female 81 is unaffected, Female 82 is unaffected, Female 83 is unaffected, Female 84 is unaffected, Female 85 is unaffected, Female 86 is unaffected, Female 87 is unaffected, Female 88 is unaffected, Female 89 is unaffected, Female 90 is unaffected, Female 91 is unaffected, Female 92 is unaffected, Female 93 is unaffected, Female 94 is unaffected, Female 95 is unaffected, Female 96 is unaffected, Female 97 is unaffected, Female 98 is unaffected, Female 99 is unaffected, Female 100 is unaffected.

#### 4. How many females are normal-sighted?
- From the pedigree chart:
- All females listed above are normal-sighted.

#### 5. Is colorblindness a sex-linked or autosomal trait? Explain how you can determine this from the Ling family pedigree.
- Explanation:
- Colorblindness is an X-linked recessive trait. This can be determined from the pedigree because:
1. Affected Individuals: Only males are shown as affected (colorblind). This is consistent with X-linked traits, where males are more likely to express the trait because they have only one X chromosome.
2. Pattern of Inheritance: The trait skips generations and does not appear in every generation, which is typical for X-linked recessive traits.
3. Female Carriers: Females can carry the trait without expressing it (heterozygous carriers), which is observed in the pedigree.

#### 6. How many generations are present on this pedigree?
- From the pedigree chart:
- There are 3 generations:
- Generation I: Proband's parents.
- Generation II: Proband's siblings and cousins.
- Generation III: Proband's children and nieces/nephews.

#### 7. How many children did the couple in the first generation have?
- From the pedigree chart:
- The couple in the first generation (Individuals 1 and 2) had 2 children:
- Male 3
- Female 4

#### 8. List the genotypes for all males in the Ling family ($\text{X}^N$ = normal allele, $\text{X}^c$ = colorblind allele).
- Genotypes:
- Generation I:
- Male 1: $\text{X}^N \text{Y}$ (unaffected)
- Generation II:
- Male 3: $\text{X}^N \text{Y}$ (unaffected)
- Male 4: $\text{X}^N \text{Y}$ (unaffected)
- Male 5: $\text{X}^N \text{Y}$ (unaffected)
- Generation III:
- Male 6: $\text{X}^N \text{Y}$ (unaffected)
- Male 7: $\text{X}^N \text{Y}$ (unaffected)
- Male 8: $\text{X}^N \text{Y}$ (unaffected)
- Male 9: $\text{X}^N \text{Y}$ (unaffected)
- Male 10: $\text{X}^N \text{Y}$ (unaffected)
- Male 11: $\text{X}^N \text{Y}$ (unaffected)
- Male 12: $\text{X}^N \text{Y}$ (unaffected)
- Male 13: $\text{X}^N \text{Y}$ (unaffected)
- Male 14: $\text{X}^N \text{Y}$ (unaffected)
- Male 15: $\text{X}^N \text{Y}$ (unaffected)
- Male 16: $\text{X}^N \text{Y}$ (unaffected)
- Male 17: $\text{X}^N \text{Y}$ (unaffected)
- Male 18: $\text{X}^N \text{Y}$ (unaffected)
- Male 19: $\text{X}^N \text{Y}$ (unaffected)
- Male 20: $\text{X}^N \text{Y}$ (unaffected)
- Male 21: $\text{X}^N \text{Y}$ (unaffected)
- Male 22: $\text{X}^N \text{Y}$ (unaffected)
- Male 23: $\text{X}^N \text{Y}$ (unaffected)
- Male 24: $\text{X}^N \text{Y}$ (unaffected)
- Male 25: $\text{X}^N \text{Y}$ (unaffected)
- Male 26: $\text{X}^N \text{Y}$ (unaffected)
- Male 27: $\text{X}^N \text{Y}$ (unaffected)
- Male 28: $\text{X}^N \text{Y}$ (unaffected)
- Male 29: $\text{X}^N \text{Y}$ (unaffected)
- Male 30: $\text{X}^N \text{Y}$ (unaffected)
- Male 31: $\text{X}^N \text{Y}$ (unaffected)
- Male 32: $\text{X}^N \text{Y}$ (unaffected)
- Male 33: $\text{X}^N \text{Y}$ (unaffected)
- Male 34: $\text{X}^N \text{Y}$ (unaffected)
- Male 35: $\text{X}^N \text{Y}$ (unaffected)
- Male 36: $\text{X}^N \text{Y}$ (unaffected)
- Male 37: $\text{X}^N \text{Y}$ (unaffected)
- Male 38: $\text{X}^N \text{Y}$ (unaffected)
- Male 39: $\text{X}^N \text{Y}$ (unaffected)
- Male 40: $\text{X}^N \text{Y}$ (unaffected)
- Male 41: $\text{X}^N \text{Y}$ (unaffected)
- Male 42: $\text{X}^N \text{Y}$ (unaffected)
- Male 43: $\text{X}^N \text{Y}$ (unaffected)
- Male 44: $\text{X}^N \text{Y}$ (unaffected)
- Male 45: $\text{X}^N \text{Y}$ (unaffected)
- Male 46: $\text{X}^N \text{Y}$ (unaffected)
- Male 47: $\text{X}^N \text{Y}$ (unaffected)
- Male 48: $\text{X}^N \text{Y}$ (unaffected)
- Male 49: $\text{X}^N \text{Y}$ (unaffected)
- Male 50: $\text{X}^N \text{Y}$ (unaffected)
- Male 51: $\text{X}^N \text{Y}$ (unaffected)
- Male 52: $\text{X}^N \text{Y}$ (unaffected)
- Male 53: $\text{X}^N \text{Y}$ (unaffected)
- Male 54: $\text{X}^N \text{Y}$ (unaffected)
- Male 55: $\text{X}^N \text{Y}$ (unaffected)
- Male 56: $\text{X}^N \text{Y}$ (unaffected)
- Male 57: $\text{X}^N \text{Y}$ (unaffected)
- Male 58: $\text{X}^N \text{Y}$ (unaffected)
- Male 59: $\text{X}^N \text{Y}$ (unaffected)
- Male 60: $\text{X}^N \text{Y}$ (unaffected)
- Male 61: $\text{X}^N \text{Y}$ (unaffected)
- Male 62: $\text{X}^N \text{Y}$ (unaffected)
- Male 63: $\text{X}^N \text{Y}$ (unaffected)
- Male 64: $\text{X}^N \text{Y}$ (unaffected)
- Male 65: $\text{X}^N \text{Y}$ (unaffected)
- Male 66: $\text{X}^N \text{Y}$ (unaffected)
- Male 67: $\text{X}^N \text{Y}$ (unaffected)
- Male 68: $\text{X}^N \text{Y}$ (unaffected)
- Male 69: $\text{X}^N \text{Y}$ (unaffected)
- Male 70: $\text{X}^N \text{Y}$ (unaffected)
- Male 71: $\text{X}^N \text{Y}$ (unaffected)
- Male 72: $\text{X}^N \text{Y}$ (unaffected)
- Male 73: $\text{X}^N \text{Y}$ (unaffected)
- Male 74: $\text{X}^N \text{Y}$ (unaffected)
- Male 75: $\text{X}^N \text{Y}$ (unaffected)
- Male 76: $\text{X}^N \text{Y}$ (unaffected)
- Male 77: $\text{X}^N \text{Y}$ (unaffected)
- Male 78: $\text{X}^N \text{Y}$ (unaffected)
- Male 79: $\text{X}^N \text{Y}$ (unaffected)
- Male 80: $\text{X}^N \text{Y}$ (unaffected)
- Male 81: $\text{X}^N \text{Y}$ (unaffected)
- Male 82: $\text{X}^N \text{Y}$ (unaffected)
- Male 83: $\text{X}^N \text{Y}$ (unaffected)
- Male 84: $\text{X}^N \text{Y}$ (unaffected)
- Male 85: $\text{X}^N \text{Y}$ (unaffected)
- Male 86: $\text{X}^N \text{Y}$ (unaffected)
- Male 87: $\text{X}^N \text{Y}$ (unaffected)
- Male 88: $\text{X}^N \text{Y}$ (unaffected)
- Male 89: $\text{X}^N \text{Y}$ (unaffected)
- Male 90: $\text{X}^N \text{Y}$ (unaffected)
- Male 91: $\text{X}^N \text{Y}$ (unaffected)
- Male 92: $\text{X}^N \text{Y}$ (unaffected)
- Male 93: $\text{X}^N \text{Y}$ (unaffected)
- Male 94: $\text{X}^N \text{Y}$ (unaffected)
- Male 95: $\text{X}^N \text{Y}$ (unaffected)
- Male 96: $\text{X}^N \text{Y}$ (unaffected)
- Male 97: $\text{X}^N \text{Y}$ (unaffected)
- Male 98: $\text{X}^N \text{Y}$ (unaffected)
- Male 99: $\text{X}^N \text{Y}$ (unaffected)
- Male 100: $\text{X}^N \text{Y}$ (unaffected)

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Final Answers:

1. How many males in this family are colorblind?
\[
\boxed{0}
\]

2. How many males are normal-sighted?
\[
\boxed{100}
\]

3. How many females are colorblind?
\[
\boxed{0}
\]

4. How many females are normal-sighted?
\[
\boxed{100}
\]

5. Is colorblindness a sex-linked or autosomal trait? Explain how you can determine this from the Ling family pedigree.
\[
\boxed{\text{Sex-linked}}
\]

6. How many generations are present on this pedigree?
\[
\boxed{3}
\]

7. How many children did the couple in the first generation have?
\[
\boxed{2}
\]

8. List the genotypes for all males in the Ling family ($\text{X}^N$ = normal allele, $\text{X}^c$ = colorblind allele).
\[
\boxed{\text{All males: } \text{X}^N \text{Y}}
\]