Instructor Notes

FIXME

RNA-seq入門RNA-seq実験では何を測定するのか?実験デザインの考察RNA-seq定量化:リードからカウントマトリックスまで参照配列の検索このワークショップで我々はどこに向かっているのか?


RStudioプロジェクトと実験データ


Rに量的データをインポートして注釈を付ける


Exploratory analysis and quality control


Differential expression analysis


Instructor Note

The function to generate a DESeqDataSet needs to be adapted depending on the input type, e.g,

R

#From SummarizedExperiment object
ddsSE <- DESeqDataSet(se, design = ~ sex + time)

#From count matrix
dds <- DESeqDataSetFromMatrix(countData = assays(se)$counts,
                              colData = colData(se),
                              design = ~ sex + time)


Instructor Note

DESeq2 uses the “Relative Log Expression” (RLE) method to calculate sample-wise size factors tĥat account for read depth and library composition. edgeR uses the “Trimmed Mean of M-Values” (TMM) method to account for library size differences and compositional effects. edgeR’s normalization factors and DESeq2’s size factors yield similar results, but are not equivalent theoretical parameters.



Instructor Note

Both of the below ways of specifying the contrast are essentially equivalent. The name parameter can be accessed using resultsNames().

R

resTime <- results(dds, contrast = c("time", "Day8", "Day0"))
resTime <- results(dds, name = "time_Day8_vs_Day0")


Extra exploration of design matrices


Gene set enrichment analysis


Next steps