A defect in dolichol phosphate biosynthesis causes a new inherited disorder with death in early infancy.
The following study describes the discovery of a new inherited metabolic disorder, dolichol kinase (DK1) deficiency. DK1 is responsible for the final step of the de novo biosynthesis of dolichol phosphate. Dolichol phosphate is involved in several glycosylation reactions, such as N-glycosylation, glycosylphosphatidylinositol (GPI)-anchor biosynthesis, and C- and O-mannosylation. We identified four patients who were homozygous for one of two mutations (c.295T-->A [99Cys-->Ser] or c.1322A-->C [441Tyr-->Ser]) in the corresponding hDK1 gene. The residual activity of mutant DK1 was 2%-4% when compared with control cells. The mutated alleles failed to complement the temperature-sensitive phenotype of DK1-deficient yeast cells, whereas the wild-type allele restored the normal growth phenotype. Affected patients present with a very severe clinical phenotype, with death in early infancy. Two of the patients died from dilative cardiomyopathy.
Kranz
Christian
C
Klinik fur Kinder und Jugendmedizin, Munster, Germany.
Jungeblut
Christoph
C
Denecke
Jonas
J
Erlekotte
Anne
A
Sohlbach
Christina
C
Debus
Volker
V
Kehl
Hans Gerd
HG
Harms
Erik
E
Reith
Anna
A
Reichel
Sonja
S
Grobe
Helfried
H
Hammersen
Gerhard
G
Schwarzer
Ulrich
U
Marquardt
Thorsten
T
D002311:Cardiomyopathy, Dilated / Q000401:mortality*; D002478:Cells, Cultured; D004252:DNA Mutational Analysis; D004288:Dolichol Phosphates / Q000096:biosynthesis*; D005260:Female; D005347:Fibroblasts / Q000201:enzymology; D005816:Genetic Complementation Test; D030342:Genetic Diseases, Inborn / Q000235:genetics / Q000378:metabolism / Q000401:mortality*; D006031:Glycosylation; D006801:Humans; D007223:Infant; D008297:Male; D009154:Mutation / Q000235:genetics*; D010375:Pedigree; D010641:Phenotype; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000172:deficiency* / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D012867:Skin / Q000166:cytology
D004288:Dolichol Phosphates; D017853:Phosphotransferases (Alcohol Group Acceptor); C020087:dolichol kinase