Dominant or Recessive

Front

Freckles: FF, Ff = Has freckles; ff = No freckles

Back

Dominant

Front

Attached earlobes: AA, Aa = Attached earlobes; aa = Free earlobes

Back

Dominant

Front

Cystic fibrosis: CC, Cc = No cystic fibrosis; cc = Has cystic fibrosis

Back

Recessive

Front

Widow's peak: WW, Ww = Widow's peak; ww = Straight hairline

Back

Dominant

Front

Red hair: RR, Rr = Not red hair; rr = Red hair

Back

Recessive

Front

Hitchhiker's thumb: HH, Hh = Hitchhiker's thumb; hh = Straight thumb

Back

Dominant

Front

Albinism: AA, Aa = Normal pigmentation; aa = Albinism

Back

Recessive

Front

Blue eyes: BB, Bb = Brown eyes; bb = Blue eyes

Back

Recessive

Front

Huntington's disease: HH = Has disease; Hh = Has disease; hh = No disease

Back

Dominant

Front

Sickle cell anemia: AA, AS = No sickle cell; SS = Has sickle cell (Note: AS is often considered a carrier with some resistance to malaria)

Back

Recessive