1. Autosomal dominant inheritance: the basics

2. AUTOSOMAL DOMINANT INHERITANCE
Parents
Parents have two copies of autosomal genes: one copy on each of a particular pair of chromosomes

3. AUTOSOMAL DOMINANT INHERITANCE
Parents
A parent with an autosomal dominant disorder has one copy of an altered gene and one normal gene of the particular pair

4. AUTOSOMAL DOMINANT INHERITANCE
Parents
Gametes
The unaffected parent passes on one or other of his/her normal genes into the eggs or sperm
The affected parent passes on either the altered gene
or the normal gene into the eggs or sperm

5. AUTOSOMAL DOMINANT INHERITANCE
Parents
Gametes
There are
four different combinations
of the two genes from each parent

6. AUTOSOMAL DOMINANT INHERITANCE
Parents
Gametes
Offspring
This child has inherited the altered gene from the affected parent and one of the normal genes from the unaffected parent

7. AUTOSOMAL DOMINANT INHERITANCE
Parents
Gametes
Offspring
This child has inherited the altered gene from the affected parent but the other normal gene from the unaffected parent

8. AUTOSOMAL DOMINANT INHERITANCE
Parents
Gametes
Offspring

9. AUTOSOMAL DOMINANT INHERITANCE
Parents
Gametes
Offspring
This child has inherited the normal gene from the affected parent and one of the normal genes from the unaffected parent

10. AUTOSOMAL DOMINANT INHERITANCE
Parents
Gametes
Offspring

11. AUTOSOMAL DOMINANT INHERITANCE
Parents
Gametes
Offspring
This child has inherited the normal gene from the affected parent and the other normal gene from the unaffected parent

12. Which children are affected by the disease?
AUTOSOMAL DOMINANT INHERITANCE
Parents
Gametes
Which children are affected by the disease?
Offspring

13. AUTOSOMAL DOMINANT INHERITANCE
Parents
Gametes
Affected
Affected
Unaffected
Unaffected

14. AUTOSOMAL DOMINANT INHERITANCE
Each child of someone with an autosomal dominant disorder therefore has a
1/2
50%
50:50
chance of inheriting the gene alteration
Affected
Unaffected