title: Power analysis of C-TDT for small sample size genome-wide association studies by the joint use of case-parent trios and pairs.
abstract: In family-based genetic association studies, it is possible to encounter missing genotype information for one of the parents. This leads to a study consisting of both case-parent trios and case-parent pairs. One of the approaches to this problem is permutation-based combined transmission disequilibrium test statistic. However, it is still unknown how powerful this test statistic is with small sample sizes. In this paper, a simulation study is carried out to estimate the power and false positive rate of this test across different sample sizes for a family-based genome-wide association study. It is observed that a statistical power of over 80% and a reasonable false positive rate estimate can be achieved even with a combination of 50 trios and 30 pairs when 2% of the SNPs are assumed to be associated. Moreover, even smaller samples provide high power when smaller percentages of SNPs are associated with the disease.
authors.affiliation: Department of Electrical and Electronic Engineering, Faculty of Engineering, Turgut Ozal University, 06010 Ankara, Turkey. frecebli@yahoo.com
authors.forename: Farid
authors.initials: F
authors.lastname: Rajabli
authors.forename: Gul
authors.initials: G
authors.lastname: Inan
authors.forename: Ozlem
authors.initials: O
authors.lastname: Ilk
mesh_terms: D019295:Computational Biology; D003198:Computer Simulation; D005190:Family; D005260:Female; D055106:Genome-Wide Association Study / Q000706:statistics & numerical data*; D005838:Genotype; D006801:Humans; D008297:Male; D015233:Models, Statistical; D009010:Monte Carlo Method; D020641:Polymorphism, Single Nucleotide; D018401:Sample Size