A novel hypomorphic ζ-chain-associated protein tyrosine kinase 70 kDa mutation with normal CD8+ T cells count

To the Editor:The z-chain-associated protein tyrosine kinase 70 kDa(ZAP70)deficiency is a rare autosomal recessive primary immunodeficiency characterized by absent CD8+T cells and non-functional CD4+T cells.[1]According to current reports,approximately 18 pathogenic ZAP70 mutations have been identified in less than 30 patients.[1-4]ZAP70 deficiency always results in recurrent bacterial,viral,and opportunistic infections,diarrhea,and autoimmune diseases.Distinctively,ZAP70 hypomorphic mutations appear to have observable clinical heterogeneity,such as Epstein-Barr virus-associated lymphoproliferative disorder/lymphoma,late-onset immunodeficiency,[3]and silent brain infarcts.[5]Hence,next-generation sequencing technology might be the predominant diagnostic approach.