title: Type 1 hyperlipoproteinemia due to a novel deletion of exons 3 and 4 in the GPIHBP1 gene.
abstract: OBJECTIVE
  Type 1 hyperlipoproteinemia is an autosomal recessive disorder characterized by severely elevated plasma triglyceride levels, which may lead to abdominal pain and pancreatitis, eruptive xanthomas and failure to thrive. Mutations in the genes encoding lipoprotein lipase (LPL), apolipoprotein CII (APOC2), apolipoprotein AV (APOA5), lipase maturing factor 1 (LMF1) or glycosylphosphatidylinositol-anchored high density lipoprotein-binding protein 1 (GPIHBP1) have been found to cause Type 1 hyperlipoproteinemia.
  
  
  METHODS
  Two sibpairs belonging to two different branches of an extended pedigree were referred for molecular elucidation for their increased plasma triglyceride levels, which untreated were >27 mmol/L. The genes LPL, APOC2, APOA5, LMF1 and GPIHBP1 were analyzed by DNA sequencing.
  
  
  RESULTS
  No mutations were found in LPL, APOC2, APOA5 or LMF1. No PCR products were obtained for exons 3 and 4 of GPIHBP1 from DNA of the 4 affected subjects. Subsequent long-range PCR revealed that the four affected were homozygous for a deletion comprising exons 3 and 4 of GPIHBP1. No increase in LPL activity was found in post-heparin plasma from the subjects.
  
  
  CONCLUSIONS
  Homozygosity for a deletion of exons 3 and 4 of GPIHBP1 results in Type 1 hyperlipoproteinemia.
authors.affiliation: Department of Medical Genetics, Oslo University Hospital Ullevaal, Oslo, Norway. Electronic address: knut.erik.berge@ous-hf.no.
authors.forename: Knut Erik
authors.initials: KE
authors.lastname: Berge
authors.affiliation: Department of Nutrition, Institute for Basic Medical Sciences, University of Oslo, Oslo, Norway; Lipid Clinic, Oslo University Hospital, Rikshospitalet, Oslo, Norway. Electronic address: kjetil.retterstol@medisin.uio.no.
authors.forename: Kjetil
authors.initials: K
authors.lastname: Retterstøl
authors.affiliation: Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, University of Gothenburg, Sweden; Department of Medical and Surgical Sciences, Clinical Nutrition Unit, University Magna Graecia of Catanzaro, Italy. Electronic address: Stefano.Romeo@wlab.gu.se.
authors.forename: Stefano
authors.initials: S
authors.lastname: Romeo
authors.affiliation: Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, University of Gothenburg, Sweden. Electronic address: Carlo.Pirazzi@wlab.gu.se.
authors.forename: Carlo
authors.initials: C
authors.lastname: Pirazzi
authors.affiliation: Department of Medical Genetics, Oslo University Hospital Ullevaal, Oslo, Norway. Electronic address: trond.paul.leren@ous-hf.no.
authors.forename: Trond P
authors.initials: TP
authors.lastname: Leren
mesh_terms: D000328:Adult; D005091:Exons / Q000235:genetics*; D005260:Female; D017353:Gene Deletion; D006801:Humans; D008072:Hyperlipoproteinemia Type I / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D018110:Receptors, Lipoprotein / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: C523701:GPIHBP1 protein, human; D018110:Receptors, Lipoprotein
keywords: Deletion; GPIHBP1; Homozygosity; Lipoprotein lipase activity; Type 1 hyperlipoproteinemia