The palpebral fissure inclination is more than two standard deviations below the mean.

Posterior positioning of the nasal root in relation to the overall facial profile for age.

Increased width of the skin of vermilion border region of upper lip.

Distance between the hairline (trichion) and the glabella (the most prominent point on the frontal bone above the root of the nose), in the midline, more than two SD below the mean. Alternatively, an apparently decreased distance between the hairline and the glabella.

Increased breadth of the nasal bridge (and with it, the nasal root).

The absence of six or more teeth from the normal series by a failure to develop.

Decreased diameter of eyebrow hairs.

Ectodermal dysplasia is a group of conditions in which there is abnormal development of the skin, hair, nails, teeth, or sweat glands.

Fragile, easily breakable hair, i.e., with reduced tensile strength.

Decreased density/number of eyelashes.

Although hypertelorism means an excessive distance between any paired organs (e.g., the nipples), the use of the word has come to be confined to ocular hypertelorism. Hypertelorism occurs as an isolated feature and is also a feature of many syndromes, e.g., Opitz G syndrome (see 300000), Greig cephalopolysyndactyly (175700), and Noonan syndrome (163950) (summary by Cohen et al., 1995).