Categorical variables were sex, affected joints(hip, knee, ankle, shoulder, elbow, wrist, small joints of the hand and foot, cervical vertebra and temporomandibular joint), laboratory findings which determines the JIA subtype(ANA, RF and HLA B27 positivity), continuous variables were the age of disease onset, the number of affected joints, ESR and CRP values at disease onset. This evidence concerns the gene ESR1 and juvenile idiopathic arthritis.