Pedigree Rules

Question 1

Autosomal recessive

Answer 1

1. Males and females equally effected
2. Unaffected individuals can have affected
   children (heterozygous carriers )
3. Can “skips generations”
4. Rare- people outside family probably don’t have
5. Becomes more common with inbreeding

Question 2

Autosomal dominant

Answer 2

1. Males and females equally affected
2. Affected individuals always have an
   affected parent (no heterozygous
   carriers—heterozygotes are affected too!)
3. Does not “skip generations”

Question 3

X-linked recessive

Answer 3

1. Males more frequently affected
2. Never transmitted from fathers to
   daughters
3. All sons of affected mothers will also
   be affected the trait
4. Can “skip generations” via female
   carriers

Question 4

X-linked dominant

Answer 4

1. Females more frequently affected
2. All of the daughters and none of the
   sons of affected fathers have the trait
3. Does not skip generations