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A review of genetics of TS appeared [in Frontiers in Neuroscience this July](http://journal.frontiersin.org/article/10.3389/fnins.2016.00351).  A new study finds heritability near 0.30, most confidently in the broadest syndrome definition \cite{27974054}.  \cite{Huang_2016}: Rare copy number variants in NRXN1 and CNTN6 increase risk for Tourette syndrome [preprint]. Covariation of tics, ADHD and OCD in a population-based adult twin study; co-occurrence of tics and OCD can be partly explained by shared etiological influences (and to some extent tics and ADHD); need more research examining sub-dimensions of these phenotypes \cite{26919823}.