Three Separate Families, One Genetic Condition
| The three pedigrees above (A, B, C) are three separate families with the same genetic condition. The shaded individuals are expressing the condition as their phenotype. Your job is to determine the mode of inheritance for this condition. Use the chart below. Signify (with a yes or no) whether or not each mode of inheritance listed in the chart is a possible mode of inheritance for that family. The mode of inheritance that is possible for all three families is probably the correct one. This shows you that it is difficult to determine the mode of inheritance for a condition using one small family. That is why researchers will hunt for several families with the same condition when trying to determine how it is inherited. | ||||||
|
X-linked dominant X-linked recessive Y-linked sex limited sex influenced male dominant sex influenced female dominant |
A
|
B
|
C
|
|||
|
This activity was taken from a workshop put on by Ball State University. It has been slightly modified for this website. Return to Family History Return to Home |
||||||