title: Further evidence for linkage of familial hyperaldosteronism type II at chromosome 7p22 in Italian as well as Australian and South American families.
abstract: BACKGROUND
  Familial hyperaldosteronism type II is a hereditary form of primary aldosteronism not attributable to the hybrid CYP11B1/CYP11B2 mutation that causes glucocorticoid remediable aldosteronism (or familial hyperaldosteronism type I). Although genetic defect(s) underlying familial hyperaldosteronism type II have not yet been elucidated, linkage to chromosome 7p22 was previously reported in two Australian families and a South American family with familial hyperaldosteronism type II.
  
  
  OBJECTIVE
  To seek evidence of linkage to chromosome 7p22 in two Italian families with familial hyperaldosteronism type II based on markers that have already yielded evidence of linkage in one South American and two Australian familial hyperaldosteronism type II families and to assess the combined multipoint logarithm of odds score in these five families (two Australian, two Italian, and one South American).
  
  
  METHODS
  Primary aldosteronism was diagnosed or excluded using widely accepted clinical and biochemical criteria. Genotypes of affected and unaffected Italian patients from two families were analysed using seven closely spaced microsatellite markers at 7p22, and multipoint logarithm of odds scores were calculated to assess linkage with familial hyperaldosteronism type II.
  
  
  RESULTS
  All known affected individuals (four and two, respectively) from each of two Italian families shared identical haplotypes for the seven markers, consistent with linkage of the disease locus with the 7p22 region. The combined multipoint logarithm of odds score for five families showing linkage at 7p22 was highly significant at 5.22 (theta = 0) for markers D7S462 and D7S517.
  
  
  CONCLUSIONS
  Linkage in two Italian families makes this the third geographical area to show linkage of familial hyperaldosteronism type II at 7p22, emphasizing the likely importance of this locus in identifying the causative mutation.
authors.affiliation: Endocrine Hypertension Research Center, University of Queensland School of Medicine, Greenslopes Hospital, Brisbane, Australia.
authors.forename: Norlela
authors.initials: N
authors.lastname: Sukor
authors.forename: Paolo
authors.initials: P
authors.lastname: Mulatero
authors.forename: Richard D
authors.initials: RD
authors.lastname: Gordon
authors.forename: Albertina
authors.initials: A
authors.lastname: So
authors.forename: David
authors.initials: D
authors.lastname: Duffy
authors.forename: Chiara
authors.initials: C
authors.lastname: Bertello
authors.forename: Livia
authors.initials: L
authors.lastname: Kelemen
authors.forename: Yvette
authors.initials: Y
authors.lastname: Jeske
authors.forename: Franco
authors.initials: F
authors.lastname: Veglio
authors.forename: Michael
authors.initials: M
authors.lastname: Stowasser
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia; D002897:Chromosomes, Human, Pair 7; D005192:Family Health; D005260:Female; D005819:Genetic Markers; D006239:Haplotypes; D006801:Humans; D006929:Hyperaldosteronism / Q000235:genetics*; D007558:Italy; D008126:Lod Score; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D010641:Phenotype; D013020:South America
chemical_list: D005819:Genetic Markers