Traits

Traits linked to MSL2

MSL complex subunit 2

The Human Phenotype Ontology links 118 traits to MSL2, by body system: features seen in people with one of the gene's rare conditions.

Abnormality of the nervous system

Trait	How often it is seen
Age-inappropriate oppositional behavior	Always
Autism	Always
Bilateral tonic-clonic seizure with generalized onset	Always
Cerebral palsy	Always
Clonus	Always
Clumsiness	Always
Degeneration of cerebellum	Always
Delayed CNS myelination	Always
Delayed motor skills	Always
EEG with burst suppression	Always
Epileptic encephalopathy	Always
Epileptic spasm	Always
Extra-axial cerebrospinal fluid accumulation	Always
Febrile seizure (within the age range of 3 months to 6 years)	Always
Focal impaired awareness seizure	Always
Hypsarrhythmia	Always
Inability to coordinate movements when walking	Always
Incoordination	Always
IQ between 34 and 49	Always
Loss of developmental milestones	Always
More active than typical	Always
Motor delay	Always
Myoclonic absence seizure	Always
Myoclonic seizure	Always
Obstructive sleep apnea	Always
Receptive language delay	Always
Repetitive movements	Always
Snoring	Always
Thin corpus callosum	Always
Waking up screaming	Always
Global developmental delay	Very often (80–99%)
Intellectual disability	Very often (80–99%)
Aggressive behavior	Often (30–79%)
Anxiety	Often (30–79%)
Autism spectrum disorder	Often (30–79%)
Cavum septum pellucidum	Often (30–79%)
Delayed speech and language development	Often (30–79%)
Echoing another person's speech	Often (30–79%)
EEG abnormality	Often (30–79%)
Epilepsy	Often (30–79%)
More grooves in brain	Often (30–79%)
Motor regression	Often (30–79%)
Periventricular nodular heterotopia	Often (30–79%)
Recurrent hand flapping	Often (30–79%)
Schizencephaly	Often (30–79%)
Self-injurious behavior	Often (30–79%)
Boiling mad	Sometimes (5–29%)
Communication delay	Sometimes (5–29%)
Spinning	Sometimes (5–29%)

Abnormality of head or neck

Trait	How often it is seen
Asymmetry of the posterior head	Always
Broad philtrum	Always
Drooling	Always
Little lower jaw	Always
Narrow jaw	Always
Smooth philtrum	Always
Webbed neck	Often (30–79%)
Abnormal fontanelle morphology	Sometimes (5–29%)
Abnormality of cranium	Sometimes (5–29%)
Abnormally small head	Sometimes (5–29%)
Big calvaria	Sometimes (5–29%)
Decreased volume of lip	Sometimes (5–29%)
Downward slanting of the opening between the eyelids	Sometimes (5–29%)
Eye folds	Sometimes (5–29%)
Frontal bossing	Sometimes (5–29%)
Long face	Sometimes (5–29%)
Narrow forehead	Sometimes (5–29%)
Receding chin	Sometimes (5–29%)
Bifid uvula	Rarely (1–4%)
Downturned corners of mouth	Rarely (1–4%)
High palate	Rarely (1–4%)
Midface retrusion	Rarely (1–4%)
Tongue tied	Rarely (1–4%)
Triangular face	Rarely (1–4%)
Upward slanting of the opening between the eyelids	Rarely (1–4%)

Abnormality of the eye

Trait	How often it is seen
Close sighted	Always
Clouding of the lens of the eye	Always
Farsightedness	Always
Severe near sightedness	Always
Wide-set eyes	Always
Deeply set eye	Often (30–79%)
Outward facing eye ball	Often (30–79%)
Abnormally close eyes	Sometimes (5–29%)
Cross-eyed	Sometimes (5–29%)
Macular hypoplasia	Sometimes (5–29%)
Abnormally small eyeball	Rarely (1–4%)

Abnormality of the musculoskeletal system

Trait	How often it is seen
Generalized decreased muscle tone	Always
Low muscle tone	Always
Low muscle tone in trunk	Always
Scoliosis	Always
Spastic diplegia	Always
Thoracic scoliosis	Always
Double-Jointed	Sometimes (5–29%)
Funnel chest	Sometimes (5–29%)

Abnormality of the digestive system

Trait	How often it is seen
Constipation	Always
Feeding difficulties	Always
Poor swallowing	Always
Inguinal hernia	Sometimes (5–29%)

Abnormality of limbs

Trait	How often it is seen
Bunion	Always
Dropped arches	Rarely (1–4%)
Slender finger	Rarely (1–4%)

Abnormality of the ear

Trait	How often it is seen
Ears rotated toward back of head	Sometimes (5–29%)
Low-set ears	Sometimes (5–29%)
Anteverted ears	Rarely (1–4%)

Abnormality of the genitourinary system

Trait	How often it is seen
Hypospadias	Always
Undescended testes	Always
Unilateral cryptorchidism	Always

Abnormality of the breast

Trait	How often it is seen
Inverted nipples	Sometimes (5–29%)
Wide-spaced nipples	Sometimes (5–29%)

Abnormality of the integument

Trait	How often it is seen
Dermal translucency	Sometimes (5–29%)
Spinal dimple	Rarely (1–4%)

Constitutional symptom

Trait	How often it is seen
Decreased ability to exercise	Always
Lack of energy and strength	Sometimes (5–29%)

Growth abnormality

Trait	How often it is seen
Obesity	Always
Tall stature	Always

Abnormality of the cardiovascular system

Trait	How often it is seen
Patent ductus arteriosus	Always

Abnormality of the endocrine system

Trait	How often it is seen
Underactive thyroid	Always

Abnormality of the immune system

Trait	How often it is seen
Baby eczema	Always

Abnormality of the respiratory system

Trait	How often it is seen
Apnea	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 MSL2 and how often each is seen. Find out more at hpo.jax.org.

One test. A lifetime of answers.

From $449Free shipping · Results in 6–8 weeks

Get my Genome Test