Table 1. The five genes directly disrupted in Tourette syndrome by unique genomic lesions.

Gene	Locus	Function	Co-morbidities	DNA lesions	Other
NRXN1a	2p21	Neurexin 1 synapse	ADHD	Two truncating deletions45	T
NRXN4/CNTNAP2b	7q35	Neurexin superfamily	OCD, MR, SD	Intragenic insertion46	c,d
IMMP2La (LRRN3)	7q31	(Neural development)	MR, SD	Two exonic deletions39, 40	T, SA, R, Dup35
CTNNA3a (LRRTM3)	10q21	(Neurexin ligand)	OCD, ADHD	Two intragenic deletions45	SA
NLGN4Xb	Xp22.33	Neurexin ligand	ASD	Truncating deletion36	XM43

Abbreviations: ADHD, attention deficit/hyperactivity disorder; ASD, autism spectrum disorder; BD, block deletion associated with TS; Dup, duplication in TS; LS, linkage region of interest; MR, mental retardation; OCD, obsessive-compulsive disorder; R, most commonly duplicated locus in ASD; SA, strong polymorphic association with ASD; SCHZ, schizophrenia; SD, speech delay; T, TS translocation breakpoint association; TS, Tourette syndrome; XM, XXX chromosome mosaicism.⁴³

^aRecurrent disruption of this gene in TS.

^bGene disruption co-segregates with disorder in TS family.

^c2p21-23 block insertion that disrupted CNTNAP2 harbours a TSAICG critical linkage region.¹¹

^dCNTNAP2 disrupted in family without TS.⁵³

Bold type indicates protein implicated in Tourette syndrome.