title: High-resolution SNP array analysis of patients with developmental disorder and normal array CGH results.
abstract: BACKGROUND
  Diagnostic analysis of patients with developmental disorders has improved over recent years largely due to the use of microarray technology. Array methods that facilitate copy number analysis have enabled the diagnosis of up to 20% more patients with previously normal karyotyping results. A substantial number of patients remain undiagnosed, however.
  
  
  RESULTS
  Using the Genome-Wide Human SNP array 6.0, we analyzed 35 patients with a developmental disorder of unknown cause and normal array comparative genomic hybridization (array CGH) results, in order to characterize previously undefined genomic aberrations. We detected no seemingly pathogenic copy number aberrations. Most of the vast amount of data produced by the array was polymorphic and non-informative. Filtering of this data, based on copy number variant (CNV) population frequencies as well as phenotypically relevant genes, enabled pinpointing regions of allelic homozygosity that included candidate genes correlating to the phenotypic features in four patients, but results could not be confirmed.
  
  
  CONCLUSIONS
  In this study, the use of an ultra high-resolution SNP array did not contribute to further diagnose patients with developmental disorders of unknown cause. The statistical power of these results is limited by the small size of the patient cohort, and interpretation of these negative results can only be applied to the patients studied here. We present the results of our study and the recurrence of clustered allelic homozygosity present in this material, as detected by the SNP 6.0 array.
authors.affiliation: Department of Pathology, Haartman Institute, University of Helsinki, Finland. linda.siggberg@helsinki.fi
authors.forename: Linda
authors.initials: L
authors.lastname: Siggberg
authors.forename: Sirpa
authors.initials: S
authors.lastname: Ala-Mello
authors.forename: Ala-Mello
authors.initials: AM
authors.lastname: Sirpa
authors.forename: Tarja
authors.initials: T
authors.lastname: Linnankivi
authors.forename: Linnankivi
authors.initials: L
authors.lastname: Tarja
authors.forename: Kristina
authors.initials: K
authors.lastname: Avela
authors.forename: Avela
authors.initials: A
authors.lastname: Kristiina
authors.forename: Ilari
authors.initials: I
authors.lastname: Scheinin
authors.forename: Scheinin
authors.initials: S
authors.lastname: Ilari
authors.forename: Kati
authors.initials: K
authors.lastname: Kristiansson
authors.forename: Kristiansson
authors.initials: K
authors.lastname: Kati
authors.forename: Päivi
authors.initials: P
authors.lastname: Lahermo
authors.forename: Lahermo
authors.initials: L
authors.lastname: Päivi
authors.forename: Marja
authors.initials: M
authors.lastname: Hietala
authors.forename: Hietala
authors.initials: H
authors.lastname: Marja
authors.forename: Lisa
authors.initials: L
authors.lastname: Metsähonkala
authors.forename: Metsähonkala
authors.initials: M
authors.lastname: Liisa
authors.forename: Esa
authors.initials: E
authors.lastname: Kuusinen
authors.forename: Kuusinen
authors.initials: K
authors.lastname: Esa
authors.forename: Maarit
authors.initials: M
authors.lastname: Laaksonen
authors.forename: Laaksonen
authors.initials: L
authors.lastname: Maarit
authors.forename: Janna
authors.initials: J
authors.lastname: Saarela
authors.forename: Saarela
authors.initials: S
authors.lastname: Janna
authors.forename: Sakari
authors.initials: S
authors.lastname: Khuutila
authors.forename: Knuutila
authors.initials: K
authors.lastname: Sakari
mesh_terms: D055028:Comparative Genomic Hybridization; D056915:DNA Copy Number Variations; D002658:Developmental Disabilities / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D018895:Microsatellite Repeats; D020411:Oligonucleotide Array Sequence Analysis; D020641:Polymorphism, Single Nucleotide; D024182:Uniparental Disomy