Table 2.

Clinical and molecular features of patients with missense BCAP31 variants.

Patient ID	Literature 2 patients 1 family (Vittal et al.)	P14 Family 13	P15 Family 14	P16 (uncle of P15) Family 14	P17 (uncle of P15) Family 14	Total 6 patients 3 families	P18 (female) Family 14 (cousin of P15, niece of P16 and P17)
Sex	M	M	M	M	M	M	F
Age last examination	21y (twins)	3y	32y	36y	29y	19y10m	19y
Variant	c.261_266del p.(Leu87_Leu89delinsPhe)	c.47T>A p.(Val16Asp)	c.338C>A p.(Ser113Tyr)	c.338C>A p.(Ser113Tyr)	c.338C>A p.(Ser113Tyr)		c.338C>A p.(Ser113Tyr)
Inheritance	mat	mat	mat	mat	mat	mat	mat
Affected carrier mother	−	SNHL	Late onset seizures	nd	nd	1 SNLH, 1 late onset seizures	Late onset seizures
Severity of ID	Moderate to severe	Mild	Severe	Severe	Moderate	Moderate to severe	Mild
Sitting	0/2	+	+	nd	+	2/4	+
Walking	0/2	−	−	−	+Ataxic	1/6	+ 17 m
Language	1/2 (partial)	+Words	+Words communicates with ipad	+Words dysarthria	+Sentences dysarthria	5/6	+Delayed dysarthria
Seizures	nd	−	−	−	−	0/4	+Drop attacks
Dystonia/chorea	2/2	+	+	+	+	6/6	−
Spasticity	nd	nd	−	+	−	1/3	−
Hearing loss	2/2	+SNHL	+Conductive	−	−	4/6	−
OFC < −2 SD	nd	−	−	+	nd	1/3	−
Elevated Liver enzyme	nd	−	−	nd	nd	0/1	nd
Unexplained episodic fever	nd	−	−	−	−	0/4	−
Age at MRI	nd	14m					18y
Abnormal MRI	1/1	−	nd	nd	nd	1/2	−
Other	Cerebral MRI showed delayed myelination, atrophy of posterior ocipital lobes, thin CC, hypoplasia of superior cerebrellar vermis	SNHL in 3 other female carriers. An uncle of P15 presumably had the same condition although DNA was not available for testing	Recurrent pneumonia. Swallowing difficulties.	Collapse due to severe dehydration and hypernatremia at 6m died at 36y of twisted bowel			Ataxic gait

Reference transcript: NM_001139441.1.

CC corpus callosum, ID intellectual disability, mat maternal, nd not determined, P patient, SNHL sensorineural hearing loss.