Family Linkage Study of Obstructive Sleep Apnea (OSA) in Iceland
Condition: Sleep Apnea Syndromes; Lung Diseases; Insulin Resistance
MeSH terms: Sleep Apnea Syndromes; Lung Diseases; Insulin Resistance
Study type: Observational

Summary: 
      To study the genetic basis of obstructive sleep apnea using a genealogical approach.
    

Detailed description: 
      BACKGROUND:

      There is family aggregation of obstructive sleep apnea (OSA) as has been shown in the United
      States, Europe and recently in Iceland. Iceland represents a unique opportunity for genetic
      research. It is a community that was settled by founders in the 9 th Century, and has
      developed in relative isolation since that time to its present size of 285,000 persons.
      Moreover, there is a commitment to record keeping that has allowed deCODE Genetics, who are
      collaborators on this grant, to develop a computerized genealogy data base that permits the
      ancestry of individuals to be traced over centuries. This tool, together with the founder
      nature of the population, makes possible a unique genealogy-driven approach to study the
      genetics of complex disorders, an approach that has already been successful.

      DESIGN NARRATIVE:

      The study uses patients with obstructive sleep apnea, who have already been diagnosed in
      Iceland where large family pedigrees have been identified. The study involves a genome-wide
      family linkage investigation. This will be conducted with an affected only approach examining
      allele sharing between affected individuals using 1,100 markers spaced across the genome. The
      investigators plan to oversample the relatively non-obese subjects providing them the
      opportunity to evaluate linkage in both relatively non-obese and obese subjects. The linkage
      study will be complemented with an association study, with unrelated cases and controls,
      matched for age, gender, and menopausal status. In the association study, they will, as a
      primary aim, test candidate genes arising from the linkage study and, as a secondary aim,
      evaluate candidate genes that they believe will be identified in the ongoing Cleveland Family
      Study. A subset of subjects in both the family linkage and association study will have
      in-depth phenotyping to determine whether there are sub-phenotypes for this complex disorder
      and, if so, whether they aggregate in families. This in depth phenotyping will involve upper
      airway magnetic resonance imaging to evaluate upper airway soft tissue and craniofacial
      structures, acoustic rhinometry to quantify nasal resistance, a known risk factor for the
      disorder, and insulin resistance. They will explore whether there are distinct patterns of
      linkage for the different sub-phenotypes. To accomplish this large genetic study, they have
      put together the resources of three major organizations--the University of Pennsylvania, the
      University of Iceland Hospitals, and deCODE Genetics. They propose to leverage the truly
      unique infrastructure developed by deCODE Genetics, the clinical research programs in sleep
      apnea at the University of Iceland Hospitals, and the in-depth phenotyping expertise at the
      University of Pennsylvania to accomplish their goals.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Sleep apnea patient cohort
      
Biospecimen description: 
      Samples with DNA