title: Reliable low-density DNA array based on allele-specific probes for detection of 118 mutations causing familial hypercholesterolemia.
abstract: BACKGROUND
  Patients with familial hypercholesterolemia (FH) have a high risk of premature cardiovascular disease (PCVD). Mutations in the LDL receptor (LDLR) gene and the R3500Q mutation in the apolipoprotein B (APOB) gene are known to cause FH, but lack of high-throughput methods makes routine genetic diagnosis difficult. The objective of this work was to develop a DNA array for large-scale identification of mutant LDLR alleles.
  
  
  METHODS
  We developed a low-density oligonucleotide microarray to identify 118 DNA sequence variations (117 for the LDLR gene and 1 for the APOB gene). We verified specificity and sensitivity by analyzing 1180 previously sequenced DNA samples, and conducted a blind study screening 407 Spanish patients with a clinical diagnosis of FH.
  
  
  RESULTS
  The DNA array confirmed the previous genotyping results in almost all cases. In the blind study, the microarray detected at least 1 mutation in 51% of the patients for whom clinical diagnosis was classified as certain according to Dutch FH-MEDPED criteria; it also identified mutations in 37% of those with a diagnosis of probable/possible FH, thus giving a definite diagnosis. Patients harboring null mutations had shorter PCVD-free survival times and higher relative risk of PCVD than patients with a missense mutation.
  
  
  CONCLUSIONS
  The proposed DNA array allows large-scale population screening and provides molecular information regarding mutation type and its correlation with clinical severity of FH, which can be used to develop therapeutic strategies.
authors.affiliation: Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Zaragoza, Spain. dtejedor@progenika.com
authors.forename: Diego
authors.initials: D
authors.lastname: Tejedor
authors.forename: Sergio
authors.initials: S
authors.lastname: Castillo
authors.forename: Pilar
authors.initials: P
authors.lastname: Mozas
authors.forename: Elisa
authors.initials: E
authors.lastname: Jiménez
authors.forename: Mónica
authors.initials: M
authors.lastname: López
authors.forename: M Teresa
authors.initials: MT
authors.lastname: Tejedor
authors.forename: Marta
authors.initials: M
authors.lastname: Artieda
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Alonso
authors.forename: Pedro
authors.initials: P
authors.lastname: Mata
authors.forename: Laureano
authors.initials: L
authors.lastname: Simón
authors.forename: Antonio
authors.initials: A
authors.lastname: Martínez
authors.forename: Miguel
authors.initials: M
authors.lastname: Pocoví
mesh_terms: D000483:Alleles; D005260:Female; D005820:Genetic Testing; D005838:Genotype; D006801:Humans; D006938:Hyperlipoproteinemia Type II / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D015345:Oligonucleotide Probes; D011973:Receptors, LDL / Q000235:genetics*; D012680:Sensitivity and Specificity
chemical_list: D015345:Oligonucleotide Probes; D011973:Receptors, LDL