Infection with Epstein–Barr virus (EBV), the causal agent of infectious mononucleosis, causes X-linked lymphoproliferative (XLP) syndromes and associated autosomal illnesses, which are severe primary immunological deficiencies. Recent results revealed important new information on the genetic and immunological causes of these disorders. They also contributed to a better understanding of the immunological processes that govern EBV infection. The majority of XLP diseases were caused by mutations in the X-linked gene SH2D1A, which encodes the signaling lymphocytic activation molecule (SLAM)-associated protein (SAP). Other genetic reasons for XLP syndromes and autosomal recessive variations of this illness had recently been discovered. Mutations in genes like XIAP, ITK, and CD27 were discovered. These individuals’ clinical signs and symptoms, as well as their immunological deficiencies, were studied.

The parallels and variations in immunological abnormalities and clinical symptoms across XLP syndromes and kindred autosomal recessive illnesses lead to critical new insights into their pathophysiology. They also aided the understanding of the processes involved in EBV infection management. CD8+ T cells, natural killer (NK) cells, and NKT cells are all thought to have a role.