text: <unk> , often called PNP-deficiency, is a rare congenital immunodeficiency of<unk><unk><unk> . This enzyme is important in the<unk>  degradation pathway. A deficiency of it causes T-cell immunodeficiency. It is also often associated with neurological disorders such as mental retardation. This autosomal recessive metabolic disorder results in severe combined immunodeficiency.
option_0: Purine nucleoside phosphorylase deficiency
option_1: Triosephosphate isomerase deficiency
option_2: Pyridoxamine 5-prime-phosphate oxidase deficiency
option_3: Carbamoyl phosphate synthetase I deficiency
option_4: Pyruvate kinase deficiency
option_5: Alpha-ketoglutarate dehydrogenase deficiency
option_6: Ornithine translocase deficiency
option_7: Fumarase deficiency