In particular, a new homogeneous group of JIA patients showing several common features (such as early onset and antinuclear antibody (ANA) positivity), which includes JIA cases previously classified into different ILAR subtypes (oJIA, RF− pJIA, PsA), has been proposed and referred to as early-onset ANA-positive JIA [22,23,24]. This evidence concerns the gene BTG3 and juvenile idiopathic arthritis.