Table 2.

Clinical details of patients with EBF3 variants

Patient	Age	Sex	Variant	Age at sitting	Age at walking	Verbal skills	Muscle tone	Additional neurological findings	Vision	Seizure	Abnormal behavior	ADD/ADHD	Brain MRI	Renal or urogenital issues	Gl
1	30 mo	M	c.191A>C p.Lys64Thr;	18 mo	Cannot walk on own, able to stand without support	Nonverbal; able to communicate with sign language	Hypotonia	Coordination issues; insensitivity/decreased sensitivity to pain; fine and gross motor difficulties	N/A	None	Moderate eye contact; did not smile until 11 mo old	N/A	N/A	Small penis	History of poor weight gain
2	24 yo	F	c.244delG, p.Val82TrpfsX50	9 mo	2 yo	Talked at 9 mo; Full sentences, normal mild articulation problems	Hypotonia	None	Strabismus, surgically repaired	None	Autistic features; tics; hallucinations (auditory and visual); emotional fragility; self- injurious behavior; hair pulling	No	Normal	Normal	Normal
3	10 yo	F	c.471C>A, p.His157Gln	1 yo	3 yo	Talked at 5 yo; normal vocabulary for age with articulation differences	Hypotonia	Fine motor difficulties; decreased pain sensitivity	Strabismus	None	Autism; tantrums and melt-downs	Hyperactivity	Normal	Vesicostomy surgery for vesicoureteral reflux and poor bladder emptying; left renal duplication; urine retention with neurogenic bladder, needs nocturnal catheter	Normal
4	11 yo	F	c.486-1G>A, IVS5-1G>A	N/A	Cannot walk on own, needs assistance or walker	Nonverbal, no words but hums tunes	Hypotonia	Muscle weakness; ataxic gait	Strabismus, surgically repaired	None	Autistic features; rubs face on hard objects to point of bruising	No	Vermis hypoplasia	Normal	Constipation; requires G- tube feeds; takes only baby foods orally
5	11 yo	F	c.616C>T, p.Arg206X	4 mo	14 mo; Wears leg braces	Talked at 10 mo; Articulation defect	Hypotonia	Hyporeflexia or difficult to elicit DTRs; mild dysmetria and gait incoordination; inconsistent sensory exam, mild proximal muscle weakness	Refractive error	None	Autism; oppositional defiant disorder	ADHD	Small schizencephalic cleft in right temporal lobe and delayed myelination at 2 yo, later resolved	History of UTIs and hydronephrosis, resolved with growth	Excess weight gain, BMI 33.5 (≫95th percentile)
6	15 mo	M	c.626G>A p.Arg209Gln	9 mo	Cannot walk at 12 mo	Babbling at 8 mo; No clear first words at 12 mo	Hypotonia	Muscle weakness; ataxic gait	Strabismus	None	Some eye contact, but no social smile	N/A	Curvilinear tract-like signal abnormality in left frontal cerebral white matter; protuberance of right optic papillae	Small penis; testes high in scrotum	Normal
7	4 yo	F	c.1402_1414del13, p.Thr464ProfsX10	8 mo	2 yo	Talked at 2 yo; Speaking in full sentences at 4 yo	Hypertonia in hips	Muscle weakness; ataxic gait	Normal	None	Oral fixation, awakens at night	No	Normal	Recurrent urinary tract infections	Normal

See Supplemental Table S1 for additional details of clinical presentations.

yo, years old; ADD, attention deficit disorder; ADHD attention deficit hyperactivity disorder; N/A, not available.