Gain of function (GOF) mutations in PIK3CD gene encoding PI3K p110δ were recently associated with a novel combined immune deficiency characterized by recurrent sinopulmonary infections, CD4 lymphopenia, reduced class-switched memory B cells, lymphadenopathy, cytomegalovirus and/or epstein-Barr virus (EBV) viremia, and EBV-related lymphoma.
Heterozygous gain of function mutations in the gene encoding p110δ subunit of PI3K have been recently associated with activated PI3K-δ syndrome (APDS), a novel combined immune deficiency characterized by recurrent sinopulmonary infections, lymphopenia, reduced class-switched memory B cells, lymphadenopathy, CMV and/or EBV viremia and EBV-related lymphoma.