Table 4. Phenotypes of individuals in the DDD study and SISu project who carry LoF variants in SETD1A.

Variant	Data set	Mode	Clinical features	Intellectual functioning
16:30977316_G/GC frameshift	DDD	Maternally inherited	Capillary hemangiomas, abnormality of the eyebrow, broad nasal tip, wide mouth, thick lower lip vermilion, short philtrum, overgrowth, renal duplication. 5.29 years old.	Delayed speech and language development.
16:30992057_CAG/C splice acceptor	DDD	Maternally inherited	Infantile axial hypotonia, delayed gross motor development, midfrontal capillary hemangioma. 0.55 years old.	Not detailed due to age
16:30992057_CAG/C splice acceptor	DDD	De novo	Mild global developmental delay, hypertelorism, wide nasal bridge, hydrocele testis. 3.14 years old.	Aggressive behavior, autoaggression. First words spoken between 2 to 2.5 years of age.
16:30992057_CAG/C splice acceptor	DDD	De novo	Global developmental delay, macrocephaly, nevus flammeus of the forehead, wide and flat nose, mandibular prognathia, hypopigmentation of the skin, wide intermammillary distance, truncal obesity. Has breath-holding attacks and night terrors. 6.09 years old.	Delayed speech and language development.
16:30977411_C/T stop gained	NFID	Case	Short stature, mild facial morphology, EEG abnormalities, delusional disorder, has psychosis.	Mental retardation
16:30977473_G/GC frameshift	NFBC	Case	Epilepsy during childhood (grand mal status epilepticus), diagnosed with personality disorder.	Not detailed

For each individual, we provide the genomic coordinates of the variant, its mode of inheritance and the study from which each patient was first recruited. ‘Clinical features’ descibes notable neuropsychiatric or neurodevelopmental symptoms in each individual and ‘intellectual functioning’ provides information on reported cognitive phenotypes. NFID, Northern Finnish Intellectual Disability study; NFBC, Northern Finnish Birth Cohort.