LYN and systemic lupus erythematosus: This phenomenon however, has not yet been explored in humans as thus far only one mutation in ZF1 has been identified (D120V) in an individual presenting with systemic lupus erythematosus (SLE), but as they also carry a likely deleterious heterozygous mutation in LYN, it is difficult to isolate the IKZF1 mutation as the sole cause of disease (57).