Of the ErGeN1 genes without a trans eQTL on proximal Chr 7, most could be partitioned into trans-bands linked to Chr 13 or 15. The regulatory hotspots underlying these trans-bands were both unique to ErGeN1 (Table 2). The Chr 13 trans-band support interval spanned from 47.6 to 69 Mb and peaked at 54.88 Mb. QTL for both cocaine induced activation [53] and hypothalamic corticotropin-releasing factor binding protein (Crf-BP) transcript abundance [54] were previously mapped to this region. Ranking the positional candidates within this region revealed a promising candidate in Sncb (Synuclein beta), a neuronal protein that is widely co-localized to presynaptic terminals throughout the brain [55]. Sncb was one of the largest ErGeN1 hub genes and was regulated by suggestive cis eQTL in both the saline and S-score datasets.
