The reference OMIM entry for this protein is 232220

Glycogen storage disease ib; gsd1b
Gsd ib
Glucose-6-phosphate transport defect

A number sign (#) is used with this entry because of evidence that type Ib glycogen storage disease (GSD1B) is caused by homozygous or compound heterozygous mutation in the G6PT1 gene (SLC37A4; 602671), which encodes glucose-6-phosphate translocase, on chromosome 11q23. Senior and Loridan (1968) proposed the existence of a second type of von Gierke disease in which, although glucose-6-phosphatase (G6PC; 613742) activity is present on in vitro assay, glucose is not liberated from glucose-6-phosphate in vivo. They referred to this as 'functional deficiency of G6P.' They pointed out that some mutants in Neurospora show impaired enzyme function in the intact fungus despite normal activity in homogenates. Arion et al. (1975) concluded that G6Pase activity requires 2 components of the microsomal membrane: (1) a glucose-6-phosphate specific transport system that shuttles G6P from the cytoplasm to the lumen of the endoplasmic reticulum (a G6P translocase), and (2) an enzyme, glucose-6-phosphate phosphohydrolase, bound to the luminal surface of the membrane. Narisawa et al. (1978) described a patient who appeared to have a defect in the transport system. In liver without detergent, enzyme activity was very low but normal activity was obtained by addition of detergent. Kuzuya et al. (1983) reported a 25-year-old patient. Protuberant abdomen and diarrhea were noted at age 1 or 2 years, and short stature and hepatomegaly at age 4 years. At age 18, yellowish-red spots appeared on her legs and hypertension was detected. At age 20, she was 138 cm tall. Eruptive xanthoma and hyperlipidemia were present. Liver scintigraphy suggested the presence of adenomas. Recurrent infections and neutropenia have been recognized as distinctive features of GSD Ib. Corbeel et al. (1983) provided a 6-year follow-up on the hematologic effects of termino-lateral portacaval anastomosis. Granulocyte counts returned to normal and recurrent infections ceased after the shunt. Platelet dysfunction, evident before surgery, was also corrected. Marked hypochromic anemia, probably caused by sequestration of iron in the spleen and resistant to therapy, was a persistent feature in this patient. The mechanism of the granulocyte defect in this disorder was discussed. Roe et al. (1986) observed Crohn disease in 2 unrelated boys with GSD Ib. Their neutrophils showed severe chronic neutropenia and markedly deficient chemotactic response, whereas the leukocytes were normal in 4 patients with GSD Ia (232200). Thus, chronic inflammatory bowel disease (IBD; see 266600) appears to be an integral part of GSD Ib and the abnormality of leukocytes is probably involved in the pathogenesis of the IBD. Oral lesions and perianal abscesses are common in this disorder (Ambruso et al., 1985). Ueno et al. (1986) found that neutrophils were defective in both motility and respiratory burst, whereas monocytes showed a defect only in respiratory burst. Bashan et al. (1988) showed that the rate of 2-deoxyglucose transport into GSD Ib polymorphonuclear leukocytes was 30% of that into cells of normal controls. Transport was normal in GSD Ib lymphocytes and in GSD Ia polymorphonuclear leukocytes and lymphocytes. The striking limitation of glucose transport across the cell membrane of polymorphonuclear leukocytes probably accounts for the impairment of leukocyte function that is characteristic of GSD Ib but not GSD Ia. Schroten et al. (1991) used granulocyte colony-stimulating factor (CSF3; 138970) to treat succes ... More on the omim web site

Subscribe to this protein entry history

June 30, 2020: Protein entry updated
Automatic update: OMIM entry 232220 was added.

Oct. 19, 2018: Additional information
Initial protein addition to the database. This entry was referenced in Bryk and co-workers. (2017).