1. Pedigree Analysis

2. Pedigree symbols 3
Female
Male
Gender unknown
Deceased n P

3. Spontaneous abortion/Miscarriage
Stillborn
Spontaneous abortion/Miscarriage
Termination of pregnancy elective reasons
Termination of pregnancy genetic/affected condition SB

4. Affected individual Proband Obligate carrier Infertility
1st person in family to come to medical/genetic attention
Obligate carrier
Infertility

5. Constructing the Pedigree
Relationship or marriage
Break in relationship
Consanguineous relationship

6. Monozygotic twins
(Identical)
Dizygotic twins
(Fraternal)

7. Adoption into a family
Adoption out of a family

8. Generations are symbolized by Roman numerals
Include below gender symbol name, maiden name if married & birthdate or age
Generations are symbolized by Roman numerals
Should give current date on pedigree I.
John Smith
Current date:

9. Other Abbreviations d. 79y dx. 41y Died at 79 years of age
Diagnosed at 41 years of age

10. I.
II.
III.
Siblings are drawn left to right in birth order

11. Rules of Thumb Always include a key At least 3 generations
Use birth dates or ages
Sign and date
Include ancestry with oldest generations

12. Causes of death or health problems should be noted on the pedigree or explained by a key52
Key Hypertension
Breast cancer

13. Autosomal Dominant Inheritance
Each affected individual has one affected parent
Males and females may be affected
Pattern of inheritance is vertical (passed from generation to generation)

14. I.
II.
III.
Autosomal Dominant Inheritance

15. Autosomal Recessive Inhertance
Do not need a parent who is affected; each parent must be a carrier of the recessive gene
Males and females may be affected
Pattern of inheritance is horizontal (usually seen in siblings)
Offspring of parent with the condition are obligate carriers

16. I.
II.
III.
Autosomal Recessive Inheritance

17. X-Linked Inhertance Gene is located on X chromosome
Female is usually clinically normal and disorders are typically seen more often in males than females
Absence of male-to-male transmission

18. I.
II.
III.
X-Linked Inheritance