Category: Genetics

Pedigree Analysis – With Tricks to Solve Different Pedigree 

Human genome is very complex and it is not possible to obtain the expected 3:1 ration in inheritance pattern. Therefore, we use pedigree analysis to study inheritance pattern in humans. A pedigree is a pictorial representation of a family history, essentially a family tree that outlines the inheritance of one or more characteristics.

In this video, I have explained six types of inheritance patterns and how to identify them with simple tricks and tips.

1. Autosomal Dominant – affected individual will always have at least one affected parent.
2. Autosomal Recessive – affected individual will have unaffected parents and skipping of generation.
3. X-Linked Dominant – affected father – all the daughters will be affected and no skipping of generation.
4. X-Linked Recessive – affected mother – all the sons are affected, criss cross inheritance – grandfather to carrier daughter to grandson.
5. Y-Linked Traits – affected father – only sons will be affected.
6. Maternal Inheritance – affected mother – all the offsprings affected and affected father – none of the offsprings affected.

00:41 Introduction

06:32 Autosomal Dominant

09:42 Autosomal Recessive

13:12 X-Linked Dominant

16:43 X-Linked Recessive

21:04 Y-Linked Traits

22:14 Maternal Inheritance

24:08 Tips and Tricks for solving any type of pedigree analysis

26:53 Examples of how to solve pedigree using these tips

Read more on this topic from a book, Modern Genetic Analysis by Anthony JF Griffiths, William M Gelbart, Jeffrey H Miller, and Richard C Lewontin here. 

Learn more about Homozygous, Heterozygous and Hemizygous – What is the Difference?