This website provides information on patients with mutations in the PIGM gene, including clinical data, molecular data, management and research options. PIGM deficiency is the firstly reported as the inherited GPI deficiencies (IGDs) in 2006.

Many eukaryotic cell-surface proteins are anchored to the membrane via glycosylphosphatidylinositol (GPI). There are at least 27 genes involved in biosynthesis and remodeling of GPI anchors. Hypomorphic coding mutations in twenty three of these genes have been reported to cause decreased expression of GPI anchored proteins on the cell surface or expression with abnormal structures of GPI-anchor and to cause autosomal or X-linked recessive forms of intellectual disability. They are called inherited GPI deficiencies (IGDs), a multisystem disorder characterized by Intellectual disability, epilepsy, encephalopathy, facial dysmorphism, organ anomalies, brachyphalangy, hypotonia, contractures and sometimes with hyperphosphatasia.

The syndrome caused by mutations in the PIGM gene is one of the IGDs and the similar symptoms as other IGDs are expected in case of affected individuals with mutations in coding region. However, there are only two case reports published until now, showing the same homozygous mutation in the promoter region of PIGM gene, the main symptoms of which are portal vein thrombosis and epilepsy without developmental delay, which is quite different from other IGDs.

Not all individuals with a mutation in the PIGM gene have these features.

This website was created to share and collect information about clinic, management and research projects to gather more knowledge and provide better treatment of patients with mutations in the PIGM gene.

Yoshiko Murakami, MD, PhD, Research Institute for Microbial Diseases Osaka University, Suita, Osaka, Japan, yoshiko@biken.osaka-u.ac.jp

Taroh Kinoshita, PhD, Research Institute for Microbial Diseases Osaka University, Suita, Osaka, Japan, tkinoshi@biken.osaka-u.ac.jp

Philippe Campeau, MD, PhD, Department of Pediatrics, CHU Sainte-Justine and University of Montreal, Montreal, QC, Canada, p.campeau@umontreal.ca

Peter Krawitz, MD, PhD, Institut für Genomische Statistik und Bioinformatik. Universitätsklinikum Bonn.  Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany, pkrawitz@uni-bonn.de

Allan Bayat, MD, Department of Epilepsy Genetics and Personalized Medicin. Danish Epilepsy Centre/University of Southern Denmark, Dianalund, Denmark, abaya@filadelfia.dk