A Simple Scalable Association Hypothesis Test Combining Gene-wide Evidence from Multiple Polymorphisms
Journal Title: Journal of Advances in Medicine and Medical Research - Year 2014, Vol 4, Issue 6
Abstract
Aims: In single-nucleotide polymorphism (SNP) scans, SNP-phenotype association hypotheses are tested, however there is biological interpretation only for genes that span multiple SNPs. We demonstrate and validate a method of combining gene-wide evidence using data for high-density lipoprotein cholesterol (HDLC). Methodology: In a family based study (N=1782 from 482 families), we used 1000 phenotype-permuted datasets to determine the correlation of z-test statistics for 592 SNP-HDLC association tests comprising 14 genes previously reported to be associated with HDLC. We generated gene-wide p-values using the distribution of the sum of correlated z-statistics. Results: Of the 14 genes, CETP was significant (p=4.0×10-5 <0.05/14), while PLTP was significant at the borderline (p=6.7×10-3 <0.1/14). These p-values were confirmed using empirical distributions of the sum of χ2 association statistics as a gold standard (2.9×10-6 and 1.8×10-3, respectively). Genewide p-values were more significant than Bonferroni-corrected p-value for the most significant SNP in 11 of 14 genes (p=0.023). Genewide p-values calculated from SNP correlations derived for 20 simulated normally distributed phenotypes reproduced those derived from the 1000 phenotype-permuted datasets were correlated with the empirical distributions (Spearman correlation = 0.92 for both). Conclusion: We have validated a simple scalable method to combine polymorphism-level evidence into gene-wide statistical evidence. High-throughput gene-wide hypothesis tests may be used in biologically interpretable genomewide association scans. Genewide association tests may be used to meaningfully replicate findings in populations with different linkage disequilibrium structure, when SNP-level replication is not expected.
Authors and Affiliations
Dhananjay Vaidya, Lisa R. Yanek, Rasika A. Mathias, Taryn F. Moy, Diane M. Becker, Lewis C. Becker
Histologically Confirmed Carcinoma of the Oesophagus; Study from the Niger Delta
Background: Carcinoma of the oesophagus is amongst the top ten cancers worldwide. It shows marked variation in incidence, types and outcome in the various regions of the world. Adenocarcinoma is the main variant worldwid...
Delirious Mania: Recognition and Successful Treatment with Donepezil
Aims: Presentation of a case of severe delirious mania with resolution of delirium after treatment with donepezil. Presentation of Case: KA was a 44 y/o Australian female with a history of bipolar affective disorder with...
Knowledge of Lassa Fever among Students of a College of Education: Call for Inclusion in Curriculum
Aims: To determine the level of knowledge of Lassa fever among students of a Federal College of Education. Study Design: A descriptive, cross-sectional study. Place and Duration of Study: Adeyemi College of Education, O...
The Lived Experiences of Persons with Vitiligo: A Phenomenological Research
Aims: This study was aimed to evaluate the lived experiences of vitiligo patients. Study Design: Descriptive phenomenological approach. Place and Duration of Study: Dermatology clinics of Zabol and Zahedan hospitals in...
Evolution and Exploration of Azadirachta indica in Dentistry: An Update
Despite great achievements globally in oral health of populations, dental caries and periodontal diseases are the most important oral health burdens particularly among under-privileged groups in developed and developing...