Human gp130 (IL6ST) is one of the most widely used chains of the cytokine receptor family. Indeed, it is involved in signal transduction of interleukin-6, interleukin-11 leukemia inhibitory factor, oncostatin M, and ciliary neurotrophic factor. In a previous report, IL6ST was assigned to chromosomes 5 and 17. Here we specify the chromosomal sub-localization of IL6ST and show that the sequence detected on 17p11 corresponds, in fact, to a nontranscribed pseudogene, whereas the active gene is located at chromosome band 5q11.