title: Epidemiological approach to identifying genetic predispositions for atypical hemolytic uremic syndrome.
abstract: Atypical hemolytic uremic syndrome (aHUS) is caused by several susceptibility genes. A registry including analyses of susceptibility genes, familial occurrence and genotype-phenotype correlation should provide classification insights. Registry data of 187 unrelated index patients included age at onset, gender, family history, relapse of aHUS and potentially triggering conditions. Mutation analyses were performed in the genes CFH, CD46 and CFI and in the six potential susceptibility genes, FHR1 to FHR5 and C4BP. Germline mutations were identified in 17% of the index cases; 12% in CFH, 3% in CD46 and 2% in CFI. Twenty-nine patients had heterozygous mutations and one each had a homozygous and compound heterozygous mutation. Mutations were not found in the genes FHR1-5 and C4BP. In 40% of the patients with familial HUS a mutation was found. Penetrance by age 45 was 50% among carriers of any mutation including results of relatives of mutation-positive index cases. The only risk factor for a mutation was family history of HUS (p = 0.02). Penetrance of aHUS in carriers of mutations is not complete. Occurrence of homo- and heterozygous mutations in the same gene suggests that the number of necessary DNA variants remains unclear. Among clinical information only familial occurrence predicts a mutation.
authors.affiliation: Department of Nephrology, University Medical Center, Albert-Ludwigs-University, Freiburg, Germany.
authors.forename: Maren
authors.initials: M
authors.lastname: Sullivan
authors.forename: Zoran
authors.initials: Z
authors.lastname: Erlic
authors.forename: Michael M
authors.initials: MM
authors.lastname: Hoffmann
authors.forename: Klaus
authors.initials: K
authors.lastname: Arbeiter
authors.forename: Ludwig
authors.initials: L
authors.lastname: Patzer
authors.forename: Klemens
authors.initials: K
authors.lastname: Budde
authors.forename: Bernd
authors.initials: B
authors.lastname: Hoppe
authors.forename: Martin
authors.initials: M
authors.lastname: Zeier
authors.forename: Karl
authors.initials: K
authors.lastname: Lhotta
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Rybicki
authors.forename: Andreas
authors.initials: A
authors.lastname: Bock
authors.forename: Gani
authors.initials: G
authors.lastname: Berisha
authors.forename: Hartmut P H
authors.initials: HP
authors.lastname: Neumann
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D002648:Child; D002675:Child, Preschool; D017242:Complement Factor H / Q000235:genetics; D017244:Complement Factor I / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D006463:Hemolytic-Uremic Syndrome / Q000453:epidemiology* / Q000235:genetics*; D006801:Humans; D007223:Infant; D008297:Male; D051916:Membrane Cofactor Protein; D008875:Middle Aged; D009154:Mutation; D019683:Penetrance; D018807:Polymorphism, Single-Stranded Conformational; D012307:Risk Factors
chemical_list: D051916:Membrane Cofactor Protein; D017242:Complement Factor H; D017244:Complement Factor I