Novel RAG2 Mutation in a Patient with Leaky Severe Combined Immunodeficiency

T and b lymphocytes development and function are highly dependent on recombination activating genes (rag) 1 and 2. rag mutations result in different degrees of t and b cell impaired function, broad clinical manifestations, and immunological manifestations. pathogenic mutations cause severe combined immunodeficiency (scid) phenotype, while hypomorphic mutations are responsible for leaky or partial scid. here, we described a 4-year-old girl who had a persistent diarrhea, recurrent infection, and vomiting. although physicians were suspicious about autoimmune enteropathy, her molecular report showed a homozygous and novel rag2 mutation in its core domain. the number of cd4 t cells and iga level were lower than normal ranges. lack of iga brought about different gi complications. our patient died finally because of liver and gallbladder failure.