Pedigree Charts

Pedigree Charts

• Show relationships within a family
• In genetics: Used to show how an

inherited trait is passed through a family

Example of Trait = Albinism

Symbols

• Circle = female
• Square = male
• Normal or without

trait = unshaded

• Trait = shaded

Symbols

• If an individual

has one
recessive allele
for a trait, the
person is a
carrier. This is
shown with a
half-shaded
square or circle.

Dropdown

The difference between a carrier and one who expresses the trait is ​

Select answer

symbol. This usually means the trait is ​

Select answer

.

Symbols

• Married couple or

couple producing
offspring =
horizontal line
connecting
midpoint of circle
and square

Symbols

• One offspring

• Multiple Offspring

How do you
differentiate between
a brother and sister
and a husband and
wife on a pedigree?

Generations

• Each generation

is (often) labeled
with a Roman
numeral.

• Oldest generation

at top of pedigree

• Current

generation at
bottom

Labelling

Label the correct parts

Drag labels to their correct position on the image

Oldest Generation

Current Generation

Expressed Trait

Multiple Choice

How do they typically label each generation?

• Roman Numerals

• Alphabetically

• Naming Parental Generation

Generations

• Individuals in

each generation
may be
numbered or
named.

• Siblings are

placed in birth
order from left to
right.

1 2

1 2 3 4 5 6

1 2 3 4 5

Multiple Choice

Who was the first person to display the trait?

• Grandfather

• Grandmother

• Parent

• Aunt

Fill in the Blanks

Fill in the Blanks

Fill in the Blanks

Drag and Drop

This trait appears to be a ​

Placeholder

trait.

Drag these tiles and drop them in the correct blank above

recessive

dominate

deadly

Fill in the Blanks

Polydactyl Trait

• Based on the

pedigree chart, is
the trait for
multiple digits
(fingers and toes)
dominant or
recessive?

• How can you tell?

Fill in the Blanks

Fill in the Blanks

Analyzing a Trait

• Sometimes a

pedigree is
drawn without
the carriers
shown.

Open Ended

Is this trait dominate or recessive? How can you tell?

Fill in the Blanks

Fill in the Blanks