BCL9 and Hand-foot syndrome: It maps to intron eight of PTPRT, a tumour suppressor gene that functions as part of the JAK/STAT pathway.40 rs1546161 was associated with hand-foot syndrome and maps to BCL9, overexpression of which has been linked to disrupted wnt signalling.41 rs1546161 is also an eQTL for GJA5, a gap junction protein with significant expression in subcutaneous adipose tissue.