The pentose phosphate pathway has two metabolic functions: (1) generation of nicotinamide adenine dinucleotide phosphate (reduced
NADPH), for reductive biosynthesis, and (2) formation of
ribose, which is an essential component of
ATP,
DNA, and
RNA. Transaldolase links the pentose phosphate pathway to
glycolysis. In patients with deficiency of transaldolase, there's an accumulation of
erythritol (from
erythrose 4-phosphate), D-
arabitol, and
ribitol. The deletion in 3 base pairs in the
TALDO1 gene results in the absence of serine at position 171 of the transaldolase protein, which is part of a highly conserved region, suggesting that the mutation causes the transaldolase deficiency that is found in
erythrocytes and
lymphoblasts. The deletion of this amino acid can lead to
liver cirrhosis and
hepatosplenomegaly (enlarged spleen and liver) during early infancy. Transaldolase is also a target of
autoimmunity in patients with
multiple sclerosis.{{cite book ==Structure==