Table 1.

Summary of mutations, detection methods and cohorts compositions for the reported patients. All genomic coordinates relate to genome build GRCh37. WES: Whole Exome Sequencing, HRM: High Resolution Melting, MIPs: Molecular Inversion Probes

Patient	Patient ID	Origin	Screening method	Cohort composition	Cohort size	mutation in genomic DNA (chr20)	mutation in cDNA (NM_015339.2)	Protein	Mutation Type	Inheritance
1	111294	Antwerp	WES	Moderate to severe intellectual disability and/or autism + dysmorphic features	10	g.49508752_49508755delTTTA	c.2496_2499delTAAA	p.Asp832Lysfs*80	Frameshift	de novo
2	11-08612	Nijmegen	WES	Non-syndromic severe intellectual disability	100	g.49510040G>T	c.1211C>A	p.Ser404*	Nonsense	de novo
3	12130.p1	Seattle	WES2,16	ASD from the Simon Simplex Collection	189	g.49510028_49510029delTT	c.1222_1223delAA	p.Lys408Valfs*31	Frameshift	de novo
4	1050237	Westmead	WES	Non-syndromic severe intellectual disability	95	g.49509086_49509098delATTTGCTCGTAAG	c.2153_2165delCTTACGAGCAAAT	p.Thr718Glyfs*12	Frameshift	de novo
5	3061-08D	Stockholm	WES	Moderate to severe intellectual disability and/or autism + dysmorphic features	45	g.49509094G>C	c.2157C>G	p.Tyr719*	Nonsense	de novo
6	122793	Antwerp	HRM	Autism	148	g.49508757_49508760delTTAA	c.2491_2494delTTAA	p.Lys831Ilefs*81	Frameshift	de novo
7	07-06960	Nijmegen	MIPs	Intellectual disability and/or autism	2743*	g.49508443delG	c.2808delC	P.Tyr936*	Frameshift	de novo
8	2376	Troina	MIPs	Intellectual disability and/or autism	2743*	g.49508757_49508760delTTAA	c.2491_2494delTTAA	p.Lys831Ilefs*81	Frameshift	de novo
9	2533	Troina	MIPs	Intellectual disability and/or autism	2743*	g.49509321G>A	c.1930C>T	p.644Arg*	Nonsense	parents not available
10	13545.p1	Seattle	MIPs16	ASD from the Simon Simplex Collection	2446	g.49509094_49509095insT	c.2156_2157insA	p.Tyr719*	Frameshift	de novo

^*patients 7, 8 and 9 from the same cohort