Tracing Traits Pedigrees

Pedigree A visual tool for following a trait through generations of a family

Why would we use a Pedigree? Pedigrees help to trace genetic diseases For example: Cystic Fibrosis This genetic disorder causes serious lung problems because of production of thickened mucus CF is a recessive trait

Reading a Pedigree Pedigrees are like maps, so you need to understand the symbol represents FEMALE represents MALE unfilled represents NOT AFFECTED filled represents AFFECTED half filled represents CARRIER

Reading a Pedigree Pedigrees are like maps, so you need to understand the symbol represent married couples represent siblings represent offspring

Reading a Pedigree

Sex-Linked Traits An allele that is on a sex chromosome. Example: Red/Green Colorblindness is a Recessive Sex-linked trait on the X chromosome So what does this mean?

Sex-Linked Traits Dominant Sex-linked traits are rare Example: Hereditary hypophosphatemic Rickets Vitamin D deficiency So what does this mean?

Selective Breeding When organisms have desirable traits and are mated with another organism with desirable traits Examples Roses Dogs