Infrequent menses (less than 6 per year or more than 35 days between cycles).

A foot where the longitudinal arch of the foot is in contact with the ground or floor when the individual is standing; or, in a patient lying supine, a foot where the arch is in contact with the surface of a flat board pressed against the sole of the foot by the examiner with a pressure similar to that expected from weight bearing; or, the height of the arch is reduced.

Clinodactyly refers to a bending or curvature of the fifth finger in the radial direction (i.e., towards the 4th finger).

Fingers that are disproportionately narrow (reduced girth) for the hand/foot size or build of the individual.

The middle finger is more than 2 SD above the mean for newborns 27 to 41 weeks EGA or above the 97th centile for children from birth to 16 years of age AND the five digits retain their normal length proportions relative to each other (i.e., it is not the case that the middle finger is the only lengthened digit), or, Fingers that appear disproportionately long compared to the palm of the hand.

Underdevelopment (hypoplasia) of the big toe.

A hole between the two bottom chambers (ventricles) of the heart. The defect is centered around the most superior aspect of the ventricular septum.

Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it.

Severe mental retardation is defined as an intelligence quotient (IQ) in the range of 20-34.

A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.

A type of ataxia characterized by the impairment of the ability to coordinate the movements required for normal walking. Gait ataxia is characteirzed by a wide-based staggering gait with a tendency to fall.

An abnormal gait pattern in which persons stand and walk with their feet spaced widely apart. This is often a component of cerebellar ataxia.

Pressing forward of the tongue in the mouth, a retained motoric habit from infantile swallowing patterns

Delayed myelination in the central nervous system.

A type of kinetic tremor that occurs during target directed movement is called intention tremor. That is, an oscillatory cerebellar ataxia that tends to be absent when the limbs are inactive and during the first part of voluntary movement but worsening as the movement continues and greater precision is required (e.g., in touching a target such as the patient's nose or a physician's finger).

Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.

Eczema is a form of dermatitis that is characterized by scaly, pruritic, erythematous lesions located on flexural surfaces.

Increase in width of the nasal tip.

Flat skin surface, with no ridge formation in the central region of the upper lip between the nasal base and upper vermilion border.

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

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).

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