→ TYPES OF PEDIGREE TRAITS
□ normal male
■ normal female
◑ carrier female w affected male offspring
◑ possible carrier female
Circles: female
Squares: male
Shaded: affected
- Must be a homozygous recessive to be affected
Unshaded: unaffected
Autosomal: associated with non-sex chromies
Autosomal Recessive → “a” albino
- Can skip gens (doesn’t have to)
- Shaded individuals are homozygous recessive
- Unshaded individuals with shaded children are heterozygous
Autosomal Dominant → “T” tongue rolling
- Can’t skip gens
- Unshaded individuals are homozygous recessive
- Shaded individuals are heterozygous or homozygous dominant
X-Linked Recessive → “Xh” hemophilia
- Can skip gens (doesn’t have to)
- Males only need one copy of gene to show trait
- If female has it, all sons will have it
- In order for female to get, father must have it and mother must be a carrier
X-Linked Dominant → “XB” brown spotted teeth
● Y-Linked
● Mitochondrial Inheritance
→ DETERMINING A TRAIT’S MODE OF INHERITANCE
When doing pedigree problems, the mode of inheritance is given to you either directly or indirectly.
“Are males and females affected equally?”
No → X-Linked trait
□ normal male
■ normal female
◑ carrier female w affected male offspring
◑ possible carrier female
Circles: female
Squares: male
Shaded: affected
- Must be a homozygous recessive to be affected
Unshaded: unaffected
Autosomal: associated with non-sex chromies
Autosomal Recessive → “a” albino
- Can skip gens (doesn’t have to)
- Shaded individuals are homozygous recessive
- Unshaded individuals with shaded children are heterozygous
Autosomal Dominant → “T” tongue rolling
- Can’t skip gens
- Unshaded individuals are homozygous recessive
- Shaded individuals are heterozygous or homozygous dominant
X-Linked Recessive → “Xh” hemophilia
- Can skip gens (doesn’t have to)
- Males only need one copy of gene to show trait
- If female has it, all sons will have it
- In order for female to get, father must have it and mother must be a carrier
X-Linked Dominant → “XB” brown spotted teeth
● Y-Linked
● Mitochondrial Inheritance
→ DETERMINING A TRAIT’S MODE OF INHERITANCE
When doing pedigree problems, the mode of inheritance is given to you either directly or indirectly.
“Are males and females affected equally?”
No → X-Linked trait
