IL1B and hyperinsulinemic hypoglycemia, familial, 4: Because the known SNP marker rs1143627 and the unannotated SNP rs549858786 have opposite effects (relative to each other) on IL1B expression, we performed an additional keyword search for [54, 63] “interleukin 1β deficiency” as a biochemical marker relevant to medicine in the NCBI databases [4].