Mapping quantitative traits with random and with ascertained sibships

Jie Peng and D. Siegmund

Department of Statistics, Stanford University, Stanford, CA 94305

Abstract:

Use of a robust score statistic based on a variance components model to map quantitative trait loci in randomly sampled pedigrees is reviewed. Sibships ascertained through a single proband are discussed. Under a standard assumption of multivariate normality, two suggested methods of ascertainment correction are shown to be asymptotically equivalent when the number of sibships is large.

Keywords: QTL, variance component, score statistics, noncentrality parameter, genome scan, ascertainment correction