Pedigree Charts (Genetics 101)
A _________________ _________________is a diagram that shows the occurrence (or
presence) of a particular trait within a family - from one generation to the next.
Below is an example of a pedigree chart. Notice the shape that represents each gender.
Draw the shape that represents a female in the pedigree chart:
________________
Draw the shape that represents a male in the pedigree chart:
________________
Pedigree for “Curved Little Finger”
Notice the roman numerals (I,II,III) to the left of the “level” on the chart. What do you think
the numerals represent?
__________________________________________________________________________
How are individuals expressing (showing) the particular trait distinguished from those not
expressing the trait?
In the space below, complete a simple Pedigree Chart representing your parents and siblings.
Remember that vertical lines connect descendants of a parental union and horizontal lines
connect both the siblings of a parental union and the parental unions themselves.
Shade in any individual that expresses “curved little fingers” in your pedigree.
Going Further . . .
On a separate sheet of paper, create a pedigree chart the includes three generations and indicates the presence of ONE
of the following traits: tongue rolling, widow’s peak, left thumb on top hand clasping, or free ear lobe.