The Interleukin-6-dependent DNA-binding protein gene (transcription factor 5: TCF5) maps to human chromosome 20 and rat chromosome 3, the IL6 receptor locus (IL6R) to human chromosome 1 and rat chromosome 2, and the rat IL6 gene to rat chromosome 4.

Using two panels of somatic cell hybrids segregating either human or rat chromosomes, the gene encoding the interleukin-6-dependent DNA-binding protein, also called liver activator protein (designated transcription factor 5: TCF5), was assigned to human chromosome 20 and to rat chromosome 3. The TCF5 gene might be identical with the NF-IL6 gene. The locus encoding the IL6 receptor gene (IL6R) was localized to human chromosome 1 and rat chromosome 2. An IL6R-like (IL6RL) locus was also assigned to human chromosome 9. In addition, the rat interleukin-6 (IL6) gene was assigned to rat chromosome 4. These mapping data allow one to extend comparison between the rat, mouse, and human gene maps.