Transaldolase deficiency: liver cirrhosis associated with a new inborn error in the pentose phosphate pathway.
This article describes the first patient with a deficiency of transaldolase (TALDO1 [E.C.2.2.1.2]). Clinically, the patient presented with liver cirrhosis and hepatosplenomegaly during early infancy. In urine and plasma, elevated concentrations of ribitol, D-arabitol, and erythritol were found. By incubating the patient's lymphoblasts and erythrocytes with ribose-5-phosphate and subsequently analyzing phosphate sugar metabolites, we discovered a deficiency of transaldolase. Sequence analysis of the transaldolase gene from this patient showed a homozygous deletion of 3 bp. This deletion results in absence of serine at position 171 of the transaldolase protein. This amino acid is invariable between species and is located in a conserved region, indicating its importance for enzyme activity. The detection of this new inborn error of pentose metabolism has implications for the diagnostic workup of liver problems of unknown etiology.
Metabolic Unit, Department of Clinical Chemistry, VU Medical Center, 1007 MB Amsterdam, The Netherlands. N.Verhoeven@AZVU.NL
N M
NM
Verhoeven
J H
JH
Huck
B
B
Roos
E A
EA
Struys
G S
GS
Salomons
A C
AC
Douwes
M S
MS
van der Knaap
C
C
Jakobs
D000595:Amino Acid Sequence; D001483:Base Sequence; D002648:Child; D002675:Child, Preschool; D017124:Conserved Sequence / Q000235:genetics; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D006720:Homozygote; D006801:Humans; D007231:Infant, Newborn; D008099:Liver / Q000473:pathology; D008103:Liver Cirrhosis / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D008214:Lymphocytes / Q000378:metabolism; D008297:Male; D008661:Metabolism, Inborn Errors / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010427:Pentose Phosphate Pathway / Q000235:genetics*; D010429:Pentoses / Q000097:blood / Q000652:urine; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012267:Ribosemonophosphates / Q000378:metabolism; D017384:Sequence Deletion / Q000235:genetics; D013154:Spleen / Q000473:pathology; D013402:Sugar Alcohols / Q000097:blood / Q000652:urine; D014153:Transaldolase / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D014174:Transketolase / Q000378:metabolism
D010429:Pentoses; D012333:RNA, Messenger; D012267:Ribosemonophosphates; D013402:Sugar Alcohols; C031626:ribose-5-phosphate; D014174:Transketolase; D014153:Transaldolase