1. HUMAN TRAITS
PHENOTYPES
AND
GENOTYPES

2. EAR LOBES
May be free or attached.
Free (A) is dominant over
attached (a).

3. BENT LITTLE FINGER
The end segment of the pinkie
finger may be straight (bb) or
bent toward your ring finger (B)

4. HITCH-HIKERS THUMB
A STRAIGHT THUMB (T)
IS DOMINANT TO A
THUMB WHICH CAN BE
BENT AT A 45º ANGLE,
HITCH-HIKER (t)

5. DIMPLES
One or more depressions in
cheek when smiling is a
dimple. (D) dimple is
dominant to no dimples (d)

6. FRECKLES
FRECKLES ARE DOMINANT
(F) TO NO FRECKLES (f)

7. WIDOW’S PEAK
Widow’s peak is dominant
(P) over straight or curved
hair lines (p).

8. TONGUE-ROLLER
Ability to roll the tongue
longitudinally is dominant
(R) to a non-roller (r)

9. TONGUE FOLDER
A folder (F) is dominant to a
non-folder (f). The tongue is
extended and the tip is bent
backwards without the aid of
your teeth or lips.

10. MID-DIGITAL HAIR
The presence of hair on the
middle segments of your
fingers (H) is dominant to no
hair (h).

11. PTC TASTER
The ability to taste
phenylthiocerbenide (PTC) is
dominant (P) to being a non-
taster (p).