1. Single-gene traits in humans

2. Chin
Dominant: Cleft
Recessive: No Cleft

3. Dimples
Dominant: Dimples
Recessive: No Dimples

4. Mid-digital hair
Dominant: mid-digital hair
Recessive: no hair

5. Freckles
Dominant: Freckles
Recessive: no freckles

6. Pinky shape
Dominant: Bent Pinky
Recessive: straight pinky

7. Thumb shape
Dominant: straight thumb
Recessive: bent thumb

8. Earlobes
Free
Attached

9. Hairline
Widow’s peak
Straight

10. Thumb crossing
Left over right
Right over left

11. Tongue roll
Tongue roller
Non-tongue roller

12. Eye color
Other color eyes
Blue eyes

13. Toe length
Second longer than big
Second shorter than big