A hybrid CFHR3-1 gene causes familial C3 glomerulopathy

J Am Soc Nephrol. 2012 Jul;23(7):1155-60. doi: 10.1681/ASN.2012020166. Epub 2012 May 24.

Abstract

Controlled activation of the complement system, a key component of innate immunity, enables destruction of pathogens with minimal damage to host tissue. Complement factor H (CFH), which inhibits complement activation, and five CFH-related proteins (CFHR1-5) compose a family of structurally related molecules. Combined deletion of CFHR3 and CFHR1 is common and confers a protective effect in IgA nephropathy. Here, we report an autosomal dominant complement-mediated GN associated with abnormal increases in copy number across the CFHR3 and CFHR1 loci. In addition to normal copies of these genes, affected individuals carry a unique hybrid CFHR3-1 gene. In addition to identifying an association between these genetic observations and complement-mediated kidney disease, these results provide insight into the protective role of the combined deletion of CFHR3 and CFHR1 in IgA nephropathy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Biopsy
  • Blood Proteins / genetics*
  • Child, Preschool
  • Chimera / genetics*
  • Complement C3 / metabolism*
  • Complement C3b Inactivator Proteins / genetics*
  • Female
  • Genetic Predisposition to Disease / genetics
  • Genotype
  • Glomerulonephritis, IGA / genetics*
  • Glomerulonephritis, IGA / metabolism*
  • Humans
  • Kidney / metabolism
  • Kidney / pathology
  • Male
  • Middle Aged
  • Pedigree

Substances

  • Blood Proteins
  • CFHR1 protein, human
  • CFHR3 protein, human
  • Complement C3
  • Complement C3b Inactivator Proteins