Contributor: Gordon K. Klintworth
Glycogenosis type Ib (glycogen storage disease type Ib, glucose-6-phosphate transporter 1 defect, OMIM #23220) is a subtype of glycogenosis type I. It has an autosomal recessive mode of inheritance and is due to a mutation in the G6PT1 gene on human chromosome 11 (11q23) and there is a defect in glucose-6-phosphate transporter in the microsomes. The manifestations of glycogenosis type Ib are more severe than those of glycogenosis type Ia and include neutropenia and neutrophil dysfunction.