SHBG and asthma: Some genes differentially expressed in other diseases coincide with genes found in this review, e.g., ZNF718 gene was found to be differentially hypermethylated in peripheral blood samples of asthma patients [39] and the promoter region of this gene was found to be differentially hypermethylated with an increase in the sex hormone-binding globulin (SHBG), a hormone associated to metabolic diseases (e.g., diabetes) [40,41].