SLE is associated with a deficiency in cluster of differentiation 247 (CD247, also known as CD3 zeta chain), a component of the T-cell receptor (TCR)-CD3 complex. A comprehensive analysis showed that in more than half of SLE patients tested CD247 expression was either attenuated or absent. Recent evidence suggests that these variations in expression profiles may be due, at least in part, to polymorphisms in the CD247 gene. Aberrant CD247 transcript variants displaying either spliced exon 7 or short 3'-untranslated region have been detected in SLE T cells, and a recent genome-wide association study reported the existence of new CD247 single-nucleotide polymorphisms in SLE patients. Here, we review these unique and significant features of defective CD247 observed in SLE.