Unconfigured Ad

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts
  • bio_informatics
    Senior Member
    • Nov 2013
    • 182

    Micro-array: Huex 1st v2

    Hello,

    This is first time I'm dealing with Micro-array data. I've affymetrix human exon arrays. Cases and control in total are 223.
    I tried few things but kind of lost in between.

    I perform rma at probe level and at core level. But the output matrix is same in both the cases is same.
    22,000 rows (one per probe) and column count is 223. I'm unable to understand why is that and how?

    Default:
    Code:
    celFiles <- list.celfiles("../CEL")
    rawData <- read.celfiles(celFiles)
    
    geneSummaries <- rma(rawData)
    PDmatrixRMA<-exprs(geneSummaries)
    getexpression_core<-as.data.frame(as.ffdf(PDmatrixRMA_core))
    write.table(getexpression_core, "PD_RMAnormalized.txt")
    Core level:
    Code:
    celFiles <- list.celfiles("../CEL")
    rawData <- read.celfiles(celFiles)
    
    geneSummaries <- rma(rawData, target="core")
    PDmatrixRMA_core<-exprs(geneSummaries)
    getexpression_core<-as.data.frame(as.ffdf(PDmatrixRMA_core))
    write.table(getexpression_core, "PD_RMAnormalized_core.txt")
    Dimensions for PD_RMAnormalized.txt and PD_RMAnormalized_core.txt are same.

    I'm assming that RMA by default normalizes at probe level.

    ?rma doesn't show me what's the default method it applies.

    other attached packages:
    [1] pd.huex.1.0.st.v2_3.14.1 DBI_0.8 RSQLite_2.1.0
    [4] ff_2.2-13 bit_1.1-12 oligo_1.42.0
    [7] Biostrings_2.46.0 XVector_0.18.0 IRanges_2.12.0
    [10] S4Vectors_0.16.0 Biobase_2.38.0 oligoClasses_1.40.0
    [13] BiocGenerics_0.24.0 dplyr_0.7.4 stringr_1.3.0

    loaded via a namespace (and not attached):
    [1] Rcpp_0.12.16 BiocInstaller_1.28.0
    [3] pillar_1.2.1 compiler_3.4.2
    [5] GenomeInfoDb_1.14.0 bindr_0.1.1
    [7] bitops_1.0-6 iterators_1.0.9
    [9] tools_3.4.2 zlibbioc_1.24.0
    [11] digest_0.6.15 memoise_1.1.0
    [13] preprocessCore_1.40.0 tibble_1.4.2
    [15] lattice_0.20-35 pkgconfig_2.0.1
    [17] rlang_0.2.0 Matrix_1.2-12
    [19] foreach_1.4.4 DelayedArray_0.4.1
    [21] bindrcpp_0.2.2 GenomeInfoDbData_1.0.0
    [23] affxparser_1.50.0 bit64_0.9-7
    [25] grid_3.4.2 glue_1.2.0
    [27] R6_2.2.2 blob_1.1.1
    [29] magrittr_1.5 splines_3.4.2
    [31] codetools_0.2-15 matrixStats_0.53.1
    [33] GenomicRanges_1.30.3 assertthat_0.2.0
    [35] SummarizedExperiment_1.8.1 stringi_1.1.7
    [37] RCurl_1.95-4.10 affyio_1.48.0
    Bioinformaticscally calm

Latest Articles

Collapse

  • SEQadmin2
    Proteomic Platforms: How to Choose the Right Analytical Strategy to Improve Detection and Clinical Applications
    by SEQadmin2


    Proteomics platforms are evolving rapidly, with advances in mass spectrometry and affinity-based approaches expanding what researchers can detect and at what scale. As the field moves toward deeper proteome coverage and clinical applications, scientists face an increasingly complex landscape of tools. This article will explore how researchers are navigating these choices to find the right platform for their work.

    The systematic characterization of the human proteome has
    ...
    07-20-2026, 11:48 AM
  • SEQadmin2
    Advanced Sequencing Platforms Tackle Neuroscience’s Toughest Genomics Problems
    by SEQadmin2



    Genomics studies in neuroscience face a special challenge due to the brain’s complexity and scarcity of samples. Mapping changes in cell type and state using conventional next-generation sequencing methods remains challenging. Advances in technologies like single-cell sequencing, spatial transcriptomics, and long-read sequencing have opened the door to deeper studies of the brain and diseases like Alzheimer’s, amyotrophic lateral sclerosis (ALS), and schizophrenia.
    ...
    07-09-2026, 11:10 AM
  • SEQadmin2
    Cancer Drug Resistance: The Lingering Barrier to Rising Survival
    by SEQadmin2



    Cancer survival rates have significantly increased in the last few decades in the United States, reaching a combined 70% 5-year survival rate by 2021. Behind this number, there are years of research to find new therapies, drug targets, and early detection methods. But there is one core challenge that keeps slowing down these advances, and it’s about drug resistance.

    There is no single reason why many patients don’t respond to treatment as expected. Cancer is...
    07-08-2026, 05:17 AM

ad_right_rmr

Collapse

News

Collapse

Topics Statistics Last Post
Started by SEQadmin2, 07-24-2026, 12:17 PM
0 responses
26 views
0 reactions
Last Post SEQadmin2  
Started by SEQadmin2, 07-23-2026, 11:41 AM
0 responses
21 views
0 reactions
Last Post SEQadmin2  
Started by SEQadmin2, 07-20-2026, 11:10 AM
0 responses
210 views
0 reactions
Last Post SEQadmin2  
Started by SEQadmin2, 07-13-2026, 10:26 AM
0 responses
78 views
0 reactions
Last Post SEQadmin2  
Working...