The diagnosis of neonatal lupus requires the presence of both of the following elements: (1) the mother has positive anti-Ro/SSA, anti-La/SSB or anti-RNP antibodies and (2) the fetus or newborn develops heart block/typical rash/hepatic or hematologic manifestations in the absence of another etiology [73]. The gene discussed is TRIM21; the disease is neonatal lupus erythematosus.