Genomic coordinate 9:36,214,441
Here I present: “Bleeding Diathesis: Thrombocytopenia“, Victor McKusick, Mendelian Inheritance in Man’, 1966. (GNE) icd10=D69.9
INTRODUCTION.
Thrombocytopenia type-12 is an autosomal recessive disorder characterized by congenital thrombocytopenia apparent from infancy or early childhood. Most affected individuals have bleeding episodes, including petechiae, easy bruising, epistaxis, hematomas, menorrhagia, and increased bleeding after trauma or surgery, although rare patients may have thrombocytopenia without bleeding. Platelets are enlarged (macrothrombocytopenia), and there is an increase of circulating immature platelets, consistent with increased production. Patient platelets show hyposialylation due to GNE mutations, which causes increased removal of platelets from the circulation, shortened platelet lifespan, and resultant thrombocytopenia. In contrast to the thrombocytopenia, which is present since birth or early childhood, features of myopathy usually do not develop until the mid-twenties, similar to Nonaka myopathy.
The GNE gene encodes UDP-N-acetylglucosamine 2-epimerase (EC 5.1.3.14) and N-acetylmannosamine kinase (EC 2.7.1.60), a bifunctional enzyme that initiates and regulates the biosynthesis of N-acetylneuraminic acid (NeuAc), a precursor of sialic acids. There is evidence that thrombocytopenia type-12 is caused mutation in the GNE gene encoded on cytogenetic location 9p13.3 and genomic coordinate 9:36,214,441.
NOTE: Cytogenetic location 9p13.3 is genomic coordinate 9:33,200,001-36,300,000.
