HAMP and nutritional disorder: Although this has not been investigated yet in TMPRSS6, it has been reported that different epigenetic regulations (e.g., histone modification, DNA methylation chromatin remodeling) play an important role in other iron sensing genes to adapt to conditions and stressors that determine the transcription of hepcidin, such as iron deficiency, inflammation, or hypoxia [39,40,41,42].