Detecting linkage for a complex disease using simulated extended pedigrees

Genet Epidemiol. 1997;14(6):981-6. doi: 10.1002/(SICI)1098-2272(1997)14:6<981::AID-GEPI70>3.0.CO;2-G.

Abstract

The simulated extended pedigree data of the Genetic Analysis Workshop 10 were used to examine the relationship between several quantitative traits (Q1-Q5), an environmental factor, age and sex and to identify genes contributing to the quantitative traits. A forward selection procedure was used to identify regression models for each trait. Residuals from these regression models were used as quantitative traits in linkage analysis. Two-point sib-pair analysis was performed on Replicate 1 of the data set using SIBPAL. Sixteen regions on 8 chromosomes yielded two-point p-values < 0.005 in Replicate 1. Two strategies for utilizing a second data set were evaluated. In a two-stage approach, only those regions with p-value < 0.005 in Replicate 1 were followed up in the second data set. Nine of these regions had p-values < 0.05 in Replicate 2; four were associated with major genes included in the generating model and the remaining five regions were false positives. An alternative strategy was to perform a repeat genome wide screen in the second data set. This strategy resulted in the identification of 20 regions with p-values < 0.05 in both replicates; five of which included major genes included in the generating model. Although the false positive rate increased when a complete genome screen was performed on both data sets, the two-stage screen, with a more stringent initial criterion for identifying suggestive linkages, had a higher rate of false negatives. For some studies, conducting two complete genome screens in a split-sample design may be worthwhile.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Age Distribution
  • Chromosome Mapping
  • Computer Simulation*
  • Environment*
  • Female
  • Genetic Diseases, Inborn / genetics*
  • Genetic Linkage*
  • Genetic Testing / methods
  • Genome, Human
  • Genotype
  • Humans
  • Male
  • Matched-Pair Analysis
  • Pedigree
  • Quantitative Trait, Heritable*
  • Regression Analysis