PTGER4 and psoriasis: As an example, our data in cell lines demonstrates a long-range interaction between psoriasis-associated SNPs and PTGER4 in the intergenic psoriasis risk locus at 5p13.3, similar to published, promoter CHi-C data in several other primary cell types, including psoriasis-relevant cells such as macrophages, monocytes, CD4+ T cells, CD8+ T cells and neutrophils [13].