Major histocompatibility complex (MHC) class I deficiency syndrome is a rare primary
immunodeficiency caused by mutations in the peptide transporter complex associated with
antigen presentation (TAP) gene which plays a crucial role in intracellular peptide antigen
presentation. A few cases have been reported to date. Recurrent sinopulmonary infections
and skin ulcers are the main characteristics of the syndrome. Here we report two siblings
diagnosed with TAP1 deficiency syndrome associated only with recurrent sinopulmonary …