Evidence map›Paper›PMID 26575185›Full record

ArticlePloS one2015

Somatic Mutation Allelic Ratio Test Using ddPCR (SMART-ddPCR): An Accurate Method for Assessment of Preferential Allelic Imbalance in Tumor DNA.

Adam J de Smith, Kyle M Walsh, Helen M Hansen, Alyson A Endicott, John K Wiencke, Catherine Metayer, Joseph L Wiemels

Open access · goldAbstract read
In one paragraph

Article in PloS one, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
0.4field-weighted citation impact, top 38% 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

4 citing papers in PubMed, 4 citations in OpenAlex.

  1. Review
  2. Article
  3. Article
  4. Review
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

7 authors at 3 institutions in 1 country.

Adam J de SmithDepartment of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America.
Kyle M WalshDivision of Neuroepidemiology, Department of Neurological Surgery, University of California San Francisco, San Francisco, California, United States of America.
Helen M HansenDivision of Neuroepidemiology, Department of Neurological Surgery, University of California San Francisco, San Francisco, California, United States of America.
Alyson A EndicottDepartment of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America.
John K WienckeDivision of Neuroepidemiology, Department of Neurological Surgery, University of California San Francisco, San Francisco, California, United States of America.
Catherine MetayerSchool of Public Health, University of California, Berkeley, California, United States of America.
Joseph L WiemelsDepartment of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America.
University of California, San Francisco · USNeurological Surgery · USUniversity of California, Berkeley · US

Funding

Environmental and Molecular Epidemiology of Childhood LeukemiaR01ES009137 · NIEHS · UNIVERSITY OF CALIFORNIA BERKELEY · PI METAYER, CATHERINE · 1999 to 2013
$21.1M
Training in Molecular& Genetic Epidemiology of CancerR25CA112355 · NCI · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI WITTE, JOHN S. · 2005 to 2018
$6.5M
Genome-Wide Association Study of Childhood Leukemia by Hispanic StatusR01CA155461 · NCI · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI MA, XIAOMEI, WIEMELS, JOSEPH LEO · 2011 to 2014
$4.1M
NCI NIH HHS R01 CA155461NCI NIH HHS R01CA155461NCI NIH HHS R25 CA112355NCI NIH HHS R25CA112355NIEHS NIH HHS R01 ES009137NIEHS NIH HHS R01ES009137
6 · The paper itself

Abstract

The extent to which heritable genetic variants can affect tumor development has yet to be fully elucidated. Tumor selection of single nucleotide polymorphism (SNP) risk alleles, a phenomenon called preferential allelic imbalance (PAI), has been demonstrated in some cancer types. We developed a novel application of digital PCR termed Somatic Mutation Allelic Ratio Test using Droplet Digital PCR (SMART-ddPCR) for accurate assessment of tumor PAI, and have applied this method to test the hypothesis that heritable SNPs associated with childhood acute lymphoblastic leukemia (ALL) may demonstrate tumor PAI. These SNPs are located at CDKN2A (rs3731217) and IKZF1 (rs4132601), genes frequently lost in ALL, and at CEBPE (rs2239633), ARID5B (rs7089424), PIP4K2A (rs10764338), and GATA3 (rs3824662), genes located on chromosomes gained in high-hyperdiploid ALL. We established thresholds of AI using constitutional DNA from SNP heterozygotes, and subsequently measured allelic copy number in tumor DNA from 19-142 heterozygote samples per SNP locus. We did not find significant tumor PAI at these loci, though CDKN2A and IKZF1 SNPs showed a trend towards preferential selection of the risk allele (p = 0.17 and p = 0.23, respectively). Using a genomic copy number control ddPCR assay, we investigated somatic copy number alterations (SCNA) underlying AI at CDKN2A and IKZF1, revealing a complex range of alterations including homozygous and hemizygous deletions and copy-neutral loss of heterozygosity, with varying degrees of clonality. Copy number estimates from ddPCR showed high agreement with those from multiplex ligation-dependent probe amplification (MLPA) assays. We demonstrate that SMART-ddPCR is a highly accurate method for investigation of tumor PAI and for assessment of the somatic alterations underlying AI. Furthermore, analysis of publicly available data from The Cancer Genome Atlas identified 16 recurrent SCNA loci that contain heritable cancer risk SNPs associated with a matching tumor type, and which represent candidate PAI regions warranting further investigation.

Indexed as

Allelic ImbalanceAllelesDNA-Binding ProteinsDNA, NeoplasmGene FrequencyGenome-Wide Association StudyGenotypeHeterozygoteHumansMultiplex Polymerase Chain ReactionPolymorphism, Single NucleotidePrecursor Cell Lymphoblastic Leukemia-LymphomaSequence Analysis, DNATranscription FactorsDNA-Binding ProteinsDNA, NeoplasmTranscription Factors

Identifiers

PMID26575185
PMCPMC4648491
OpenAlexW2175489923

What OpenQuestion holds

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LicenceCC BY
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Registered trials

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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.