Abnormally small penis. At birth, the normal penis is about 3 cm (stretched length from pubic tubercle to tip of penis) with micropenis less than 2.0-2.5 cm.

A finger resting on the dorsal surface of an adjacent digit when the hand is at rest.

An abnormal restriction of fetal growth with fetal weight below the tenth percentile for gestational age.

A type of hearing impairment in one or both ears related to an abnormal functionality of the cochlear nerve.

Upper insertion of the ear to the scalp below an imaginary horizontal line drawn between the inner canthi of the eye and extending posteriorly to the ear.

A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.

Pachygyria is a malformation of cortical development with abnormally wide gyri with sulci 1,5-3 cm apart and abnormally thick cortex measuring more than 5 mm (radiological definition). See also neuropathological definitions for 2-, 3-, and 4-layered lissencephaly.

Underdevelopment of the corpus callosum.

Underdevelopment of the vermis of cerebellum.

An abnormality of the cerebral cortex with fewer gyri but with normal cortical thickness. This pattern is usually often associated with congenital microcephaly.

Reduced amount of myelin in the central nervous system resulting from defective myelinogenesis.

Partial or complete wasting (loss) of brain tissue that was once present.

Head circumference below 2 standard deviations below the mean for age and gender.

An increased susceptibility to lower respiratory tract infections as manifested by a history of recurrent lower respiratory tract infections.

A type of primary immune deficiency that is characterized by a more severe defect in both the T- and B-lymphocyte systems.

An abnormal decrease from the normal count of B cells.

An abnormally low count of T cells.

An anomaly of the natural killer cell, which is a lymphocyte that can spontaneously kill a variety of target cells without prior antigenic activation via germline encoded activation receptors. It also regulates immune responses via cytokine release and direct contact with other cells.

Forward prominence of the entire forehead, due to protrusion of the frontal bone.

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

Distance between nasal base and midline upper lip vermilion border more than 2 SD above the mean. Alternatively, an apparently increased distance between nasal base and midline upper lip vermilion border.

Height of the vermilion of the upper lip in the midline more than 2 SD below the mean. Alternatively, an apparently reduced height of the vermilion of the upper lip in the frontal view (subjective).

Recurrent episodes of ulceration of the oral mucosa, typically presenting as painful, sharply circumscribed fibrin-covered mucosal defects with a hyperemic border.

Decreased vertical distance from the vermilion border of the lower lip to the inferior-most point of the chin.

An eye that is more deeply recessed into the plane of the face than is typical.

Visual impairment (or vision impairment) is vision loss (of a person) to such a degree as to qualify as an additional support need through a significant limitation of visual capability resulting from either disease, trauma, or congenital or degenerative conditions that cannot be corrected by conventional means, such as refractive correction, medication, or surgery.