To find a ridge, place your hand at the base of your neck where it joins your shoulders, and on the center line of your spine. Run your fingers straight up your neck toward your head. If you have a ridge, it will stop your fingers from going on up and across your head. The back of the teeth also curve outward rather than straight as the descendants of anglo-saxon parentage do. Teeth like these are called Asian Shovel Teeth.
Some descendants have what is called an Asian eyefold.
This is rather difficult to describe. At the inner corner of the eye, the upper lid attaches slightly lower than the lower lid. That is to say that it overlaps the bottom lid. If you place your finger just under the inner corner of the eye and gently pull down, a wrinkle will form which makes the fold more visible. Some families may have members with fairly dark skin who suffer with vitiligo, a loss of pigmentation, leaving the skin blotched with white patches.