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Family-based association test using normal approximation to gene dropping null distribution.

ABSTRACT: We derive the analytical mean and variance of the score test statistic in gene-dropping simulations and approximate the null distribution of the test statistic by a normal distribution. We provide insights into the gene-dropping test by decomposing the test statistic into two components: the first component provides information about linkage, and the second component provides information about fine mapping under the linkage peak. We demonstrate our theoretical findings by applying the gene-dropping test to the simulated data set from Genetic Analysis Workshop 18 and comparing its performance with existing population and family-based association tests.

SUBMITTER: Jiang Y

PROVIDER: S-EPMC4143692 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Family-based association test using normal approximation to gene dropping null distribution.

Jiang Yuan Y Emerson Sarah S Wang Lu L Li Lujing L Di Yanming Y

BMC proceedings 20140617 Suppl 1

We derive the analytical mean and variance of the score test statistic in gene-dropping simulations and approximate the null distribution of the test statistic by a normal distribution. We provide insights into the gene-dropping test by decomposing the test statistic into two components: the first component provides information about linkage, and the second component provides information about fine mapping under the linkage peak. We demonstrate our theoretical findings by applying the gene-dropp ...[more]

PMID: 25519313

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