title: Accounting for relatedness in family-based association studies: application to Genetic Analysis Workshop 18 data.
abstract: In the last few years, a bewildering variety of methods/software packages that use linear mixed models to account for sample relatedness on the basis of genome-wide genomic information have been proposed. We compared these approaches as implemented in the programs EMMAX, FaST-LMM, Gemma, and GenABEL (FASTA/GRAMMAR-Gamma) on the Genetic Analysis Workshop 18 data. All methods performed quite similarly and were successful in reducing the genomic control inflation factor to reasonable levels, particularly when the mean values of the observations were used, although more variation was observed when data from each time point were used individually. From a practical point of view, we conclude that it makes little difference to the results which method/software package is used, and the user can make the choice of package on the basis of personal taste or computational speed/convenience.
authors.affiliation: Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, UK ; Division of Medical Genetics, Department of Internal Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Rama VI Rd, Ratchathevi, Bangkok 10400, Thailand.
authors.forename: Jakris
authors.initials: J
authors.lastname: Eu-Ahsunthornwattana
authors.affiliation: Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, UK.
authors.forename: Richard Aj
authors.initials: RA
authors.lastname: Howey
authors.affiliation: Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, UK.
authors.forename: Heather J
authors.initials: HJ
authors.lastname: Cordell