In this study, urine properdin exhibits similar diagnostic characteristics as PF-4, in that it has the ability to distinguish active LN in both ethnic groups of patients, but with the best performance being noted among African-American LN patients, in whom urine properdin exhibited the highest specificity and NPV values in identifying active LN patients, compared to other competing markers and conventional yardsticks. The gene discussed is CFP; the disease is lobular neoplasia.