Pedigrees & Patterns of Genetic Inheritance

Before you watch this video you should really watch the previous video in the section which covers Types of Inheritance

Pedigrees are graphical representations of ancestry with respect to one or more disease(s). Males are represented with a square while females are represented with a circle. The shape is black/filled in if the individual is affected by the disease. The shape is empty/white if the individual is not affected by the disease (may be unaffected or carrier). Usually each generation (row) is labeled with a roman numeral while each individual is labeled with a number.

Pedigree Autosomal Dominant Recessive Mitochondrial X Linked Recessive

 Autosomal Dominant Pedigree

Autosomal Dominant Pedigree

 

Autosomal Recessive Pedigree

Autosomal Recessive Pedigree

 

X-Linked Recessive Pedigree

X Linked Recessive Pedigree

 

Mitochondrial Inheritance Pedigree

Mitochondrial Inheritance Pedigree

Now that you are done with this video you should check out the next video in the Genetics section which covers Purine Salvage Pathway & Lesch-Nyhan Syndrome.

11 thoughts on “Pedigrees & Patterns of Genetic Inheritance”

  1. my name is scott . you are amazing. I thank you so much. I have failed step 1 in part because I did not concentrate on high yield material. I under estimated the size of this exam. I am studying again for this monster. wish me luck.

  2. Bruhh!!! Thank you soo much mann…. this stuff was very confusing to me but you made it bearable… with much practice i believe i will get it.

  3. If a pedigree chart shows both parents dying (empty box and circle with a line drawn through them) do you assume that this is the result of the trait? Btw, thank you for the explanations and examples! They really help! I’m not taking Step 1 because I live in the Caribbean but your content is still helping me study for my upcoming test.

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