Understanding a pedigree
Doctors can use a pedigree to show how genetic disorders are inherited in a family. They can use this to work out the probability that someone in a family will inherit a condition.
In order to understand the following presentations on inheritance patterns, you may find it useful to spend a few moments looking at the images below and familiarising yourselves with the meanings of the symbols and connecting lines used to draw pedigrees.
Please note - this table is best viewed in landscape mode when viewing this step on a mobile device.
|Angled lines above||Twins|
|Two lines between||Consanguineous couple|
|A small circle inside a larger circle/square||Carrier|
|Line diagonally through symbol||Individual is deceased|
Once you have seen some examples, you may wish to draw your own family pedigree and see the results.
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