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## Etiology  The most important genetics news of the year may have been the presentation by Huang and colleagues at the Tourette World Congress in London this June, reporting on a large collaborative study of copy number variants (CNVs) in approximately 2,500 TS cases and 3,500 controls \citep{Huang:London}. They first tested some CNVs previously reported in various neurological and psychiatric illnesses; the most significant confirmation in this sample was of exonic deletions in _NRXN1_, a gene previously implicated in autism and TS \citep*{24578685}. They also searched for new, large CNVs and identified a novel TS locus, _CNTN6_, that was significant at a whole-genome level by permutation testing. This gene and 4 of the 32 next most likely candidates this analysis identified are neural adhesion molecules \citep{24578685}. \citep*{24578685}.  _CNTN6_ is a reasonable candidate for etiologically contributing to TS; its expression in the brain varies during development \citep{18046458}, knockout mice show motor deficits \citep{12884264}, and an independent study found a variety of neurological and psychiatric symptoms (including 2 with OCD) in 14 patients identified by _CNTN6_ CNVs \citep{26257835}. Fewer than 1% of TS cases in this sample had CNVs in _CNTN6_, so its overall importance in TS remains to be more fully characterized. Additional genetic studies of interest are listed in the table, below.