Traits

Traits linked to MARK2

microtubule affinity regulating kinase 2

The Human Phenotype Ontology links 80 traits to MARK2, by body system: features seen in people with one of the gene's rare conditions.

Abnormality of head or neck

Trait	How often it is seen
Relatively large head	Always
Downward slanting of the opening between the eyelids	Often (30–79%)
Full lips	Often (30–79%)
Narrow face	Often (30–79%)
Broad forehead	Sometimes (5–29%)
Broad philtrum	Sometimes (5–29%)
Bulbous nose	Sometimes (5–29%)
Deep philtrum	Sometimes (5–29%)
Eye folds	Sometimes (5–29%)
High forehead	Sometimes (5–29%)
Long philtrum	Sometimes (5–29%)
Nasal tip, upturned	Sometimes (5–29%)
Prominent forehead	Sometimes (5–29%)
Prominent nasal tip	Sometimes (5–29%)
Prominent nose	Sometimes (5–29%)
Short philtrum	Sometimes (5–29%)
Slender nose	Sometimes (5–29%)
Wide nasal bridge	Sometimes (5–29%)
Corners of eye widely separated	Rarely (1–4%)
Hooded upper eyelid	Rarely (1–4%)
Long eyelashes	Rarely (1–4%)
Monobrow	Rarely (1–4%)
Short opening between the eyelids	Rarely (1–4%)
Sparse eyebrow	Rarely (1–4%)

Abnormality of the nervous system

Trait	How often it is seen
Age-inappropriate oppositional behavior	Always
Aggressive behavior	Always
Agitation	Always
Anxiety	Always
Attention deficit	Always
Brisk reflexes	Always
Delayed speech and language development	Always
Intellectual disability	Always
Repetitive movements	Always
Weakness of one side of body	Always
Autism spectrum disorder	Very often (80–99%)
Global developmental delay	Very often (80–99%)
Cognitive regression	Often (30–79%)
Difficulty staying or falling asleep	Often (30–79%)
EEG abnormality	Often (30–79%)
Epilepsy	Often (30–79%)
Motor delay	Often (30–79%)
Pauses in breathing while sleeping	Often (30–79%)
Difficulty sleeping	Sometimes (5–29%)

Abnormality of the eye

Trait	How often it is seen
Deeply set eye	Often (30–79%)
Close sighted	Sometimes (5–29%)
Cross-eyed	Sometimes (5–29%)
Wide-set eyes	Sometimes (5–29%)
Abnormally small eyeball	Rarely (1–4%)
Astigmatism	Rarely (1–4%)
Drooping upper eyelid	Rarely (1–4%)
Farsightedness	Rarely (1–4%)
Stellate iris	Rarely (1–4%)

Abnormality of the ear

Trait	How often it is seen
Abnormal helix morphology	Often (30–79%)
Ears rotated toward back of head	Sometimes (5–29%)
Large ears	Sometimes (5–29%)
Low-set ears	Sometimes (5–29%)
Overfolded ears	Sometimes (5–29%)
Prominent ear	Sometimes (5–29%)
Thickened helices	Sometimes (5–29%)
Hearing impairment	Rarely (1–4%)

Abnormality of the musculoskeletal system

Trait	How often it is seen
Hypermobility of all joints	Always
Low muscle tone	Always
Double-Jointed	Sometimes (5–29%)
Thoracic scoliosis	Sometimes (5–29%)
Abnormal formation of the hip	Rarely (1–4%)
Hunched back	Rarely (1–4%)

Abnormality of the digestive system

Trait	How often it is seen
Acid reflux	Rarely (1–4%)
Birth defect in which part of esophagus did not develop	Rarely (1–4%)
Chronic constipation	Rarely (1–4%)
Episodic vomiting	Rarely (1–4%)

Abnormality of the genitourinary system

Trait	How often it is seen
Glanular hypospadias	Always
Hypospadias	Sometimes (5–29%)
Phimosis	Rarely (1–4%)

Abnormality of limbs

Trait	How often it is seen
Broad big toe	Rarely (1–4%)
Webbed fingers or toes	Rarely (1–4%)

Abnormality of blood and blood-forming tissues

Trait	How often it is seen
Bloody nose	Always

Abnormality of the endocrine system

Trait	How often it is seen
Underactive thyroid	Always

Abnormality of the integument

Trait	How often it is seen
Excessive hair growth	Always

Growth abnormality

Trait	How often it is seen
Short stature	Sometimes (5–29%)

Laboratory abnormality

Trait	How often it is seen
High blood calcium levels	Always

How often is among people with one of the gene's conditions, the most often across them, as the Human Phenotype Ontology records it. These pages describe traits and the research behind them; they are not a diagnosis, and a doctor or genetic counsellor is the person to ask about symptoms.

Where this comes from

The Human Phenotype Ontology, release 2026-09-01: the traits linked to MARK2 and how often each is seen. Find out more at hpo.jax.org.

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