- Joint hypermobility (HP:0001382): The capability that a joint (or a group of joints) has to move, passively and/or actively, beyond normal limits along physiological axes. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2891)
- Ataxia (HP:0001251): Ataxia refers to impaired coordination of voluntary muscle movement. Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly). Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2891)
- Global developmental delay (HP:0001263): 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. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2891)
- Growth delay (HP:0001510): A deficiency or slowing down of growth pre- and postnatally. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2891)
- Pili torti (HP:0003777): Pili (from Latin pilus, hair) torti (from Latin tortus, twisted) refers to short and brittle hairs that appear flattened and twisted when viewed through a microscope. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2891)
- Abnormality of hair texture (HP:0010719): An abnormality of the texture of the hair. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2891)
- Aplasia/Hypoplasia of the eyebrow (HP:0100840): Absence or underdevelopment of the eyebrow. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2891)
- Sparse or absent eyelashes (HP:0200102). Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2891)
- Hypotonia (HP:0001252): 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. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2891)
- Gait disturbance (HP:0001288): The term gait disturbance can refer to any disruption of the ability to walk. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2891)
These phenotypes are associated with the disease Pili torti-developmental delay-neurological abnormalities syndrome (ORPHA:2891).