Evidence map›Paper›PMID 21735171›Full record

ArticleHuman genetics2012

Artifact due to differential error when cases and controls are imputed from different platforms.

Jennifer A Sinnott, Peter Kraft

Abstract readComparative Study
In one paragraph

Article in Human genetics, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 22 papers, 3 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
22citing papers in PubMed, 3 pooled it
3.2field-weighted citation impact, top 8% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

22 citing papers in PubMed, 3 syntheses or guidelines pooled it, 36 citations in OpenAlex.

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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

2 authors at 1 institution in 1 country.

Jennifer A SinnottDepartment of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA. jsinnott@hsph.harvard.edu
Peter Kraft
Harvard University · US

Funding

Statistical Methods for Analysis of Massive Genetic and Genomic Data in Cancer ResearchR35CA197449 · NCI · HARVARD UNIVERSITY D/B/A HARVARD SCHOOL OF PUBLIC HEALTH · PI XIHONG LIN · 2015 to 2026
$10.9M
Characterizing Genetic Susceptibility to Breast and Prostate Cancer; the BPC3U01CA098233 · NCI · BRIGHAM AND WOMEN'S HOSPITAL · PI HUNTER, DAVID JOHN · 2003 to 2010
$10.8M
Joint Interdisciplinary Training Program in Biostatistics & Computational BiologyT32GM074897 · NIGMS · HARVARD UNIVERSITY (SCH OF PUBLIC HLTH) · PI HUTTENHOWER, CURTIS, LIN, XIHONG · 2005 to 2019
$3.7M
Genes and Environment Initiatives in Type 2 DiabetesU01HG004399 · NHGRI · HARVARD SCHOOL OF PUBLIC HEALTH · PI HU, FRANK B · 2007 to 2008
$1.2M
NCI NIH HHS R35 CA197449NCI NIH HHS U01 CA098233NHGRI NIH HHS U01 HG004399NIGMS NIH HHS T32 GM074897
6 · The paper itself

Abstract

Including previously genotyped controls in a genome-wide association study can provide cost-savings, but can also create design biases. When cases and controls are genotyped on different platforms, the imputation needed to provide genome-wide coverage will introduce differential measurement error and may lead to false positives. We compared genotype frequencies of two healthy control groups from the Nurses' Health Study genotyped on different platforms [Affymetrix 6.0 (n = 1,672) and Illumina HumanHap550 (n = 1,038)]. Using standard imputation quality filters, we observed 9,841 single-nucleotide polymorphisms (SNPs) out of 2,347,809 (0.4%) significant at the 5 × 10(-8) level. We explored three methods for controlling for this Type I error inflation. One method was to remove platform effects using principal components; another was to restrict to SNPs of highest quality imputation; and a third was to genotype some controls alongside cases to exclude SNPs that are statistical artifact. The first method could not reduce the Type I error rate; the other two could dramatically reduce the error rate, although both required that a portion of SNPs be excluded from analysis. Ideally, the biases we describe would be eliminated at the design stage, by genotyping sufficient numbers of cases and controls on each platform. Researchers using imputation to combine samples genotyped on different platforms with severely unbalanced case-control ratios should be aware of the potential for inflated Type I error rates and apply appropriate quality filters. Every SNP found with genome-wide significance should be validated on another platform to verify that its significance is not an artifact of study design.

Indexed as

ArtifactsOligonucleotide Array Sequence AnalysisAlgorithmsBreast NeoplasmsCase-Control StudiesDiabetes Mellitus, Type 2DNAFemaleGene FrequencyGenetic MarkersGenome, HumanGenome-Wide Association StudyGenotypeHumansPolymerase Chain ReactionPolymorphism, Single NucleotideDNAGenetic Markers

Identifiers

PMID21735171
PMCPMC3217156
OpenAlexW2094278899

What OpenQuestion holds

Textmetadata
LicenceTDM
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.