Last data update: 2014.03.03

R: Output Significant Genes
topGeneR Documentation

Output Significant Genes

Description

Identify differentially expressed genes using rank product method

Usage


     topGene(x,cutoff=NULL,method="pfp",num.gene=NULL,logged=TRUE,logbase=2,gene.names=NULL)

Arguments

x

the value returned by the function RP, RP.advance or Rsum.advance

cutoff

threshold in pfp used to select genes

method

If cutoff is provided, the method needs to be selected to identify genes."pfp" uses percentage of false prediction, which is the default setting. "pval" used p-value which is less stringent than pfp

num.gene

number of candidate genes of interests, if cutoff is provided, this will be ignored

logged

if "TRUE", data has bee logged, otherwise set it to "FALSE"

logbase

base used when taking log, used to restore the fold change.The default value is 2, this will be ignored if logged=FALSE

gene.names

if "NULL", no gene name will be attached to the output table

Value

Two tables of identified genes with gene.index: index of gene in the original data set RP/Rsum: Computed rank product/sum for each gene FC:(class1/class2): Expression Fold change of class 1/ class 2. pfp: estimated pfp for each gene if the gene is used as cutoff point P.value: estimated p-value for each gene

Table 1 list genes that are up-regulated under class 2, Table 1 ist genes that are down-regulated under class 2,

Author(s)

Fangxin Hong fhong@salk.edu

References

Breitling, R., Armengaud, P., Amtmann, A., and Herzyk, P.(2004) Rank Products: A simple, yet powerful, new method to detect differentially regulated genes in replicated microarray experiments, FEBS Letter, 57383-92

See Also

plotRP RP RPadvance RSadvance

Examples


      # Load the data of Golub et al. (1999). data(golub) 
      # contains a 3051x38 gene expression
      # matrix called golub, a vector of length called golub.cl 
      # that consists of the 38 class labels,
      # and a matrix called golub.gnames whose third column 
      # contains the gene names.
      data(golub)

      #use a subset of data as example, apply the rank 
      #product method
      subset <- c(1:4,28:30)
      #Setting rand=123, to make the results reproducible,

      #identify genes 
      RP.out <- RP(golub[,subset],golub.cl[subset],rand=123)  

      #get two lists of differentially expressed genes 
      #by setting FDR (false discivery rate) =0.05

      table=topGene(RP.out,cutoff=0.05,method="pfp",logged=TRUE,logbase=2,
                   gene.names=golub.gnames[,3])
      table$Table1
      table$Table2

      #using pvalue<0.05
      topGene(RP.out,cutoff=0.05,method="pval",logged=TRUE,logbase=2,
                   gene.names=golub.gnames[,3])

      #by selecting top 10 genes

      topGene(RP.out,num.gene=10,gene.names=golub.gnames[,3])

Results


R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> library(RankProd)
> png(filename="/home/ddbj/snapshot/RGM3/R_BC/result/RankProd/topGene.Rd_%03d_medium.png", width=480, height=480)
> ### Name: topGene
> ### Title: Output Significant Genes
> ### Aliases: topGene
> ### Keywords: htest
> 
> ### ** Examples
> 
> 
>       # Load the data of Golub et al. (1999). data(golub) 
>       # contains a 3051x38 gene expression
>       # matrix called golub, a vector of length called golub.cl 
>       # that consists of the 38 class labels,
>       # and a matrix called golub.gnames whose third column 
>       # contains the gene names.
>       data(golub)
> 
>       #use a subset of data as example, apply the rank 
>       #product method
>       subset <- c(1:4,28:30)
>       #Setting rand=123, to make the results reproducible,
> 
>       #identify genes 
>       RP.out <- RP(golub[,subset],golub.cl[subset],rand=123)  
Rank Product analysis for two-class case 
 
Starting 100 permutations... 
Computing pfp .. 
Outputing the results .. 
> 
>       #get two lists of differentially expressed genes 
>       #by setting FDR (false discivery rate) =0.05
> 
>       table=topGene(RP.out,cutoff=0.05,method="pfp",logged=TRUE,logbase=2,
+                    gene.names=golub.gnames[,3])
Table1: Genes called significant under class1 < class2 

Table2: Genes called significant under class1 > class2 

>       table$Table1
                 gene.index RP/Rsum FC:(class1/class2)    pfp P.value
HG3494-HT3688_at        436  7.3165             0.2369 0.0200   0e+00
HG2724-HT2820_at        418  7.9323             0.2689 0.0100   0e+00
D87116_at               346  8.2189             0.2605 0.0067   0e+00
HG987-HT987_at          475  8.5880             0.3031 0.0100   1e-04
D88422_at               378 10.2910             0.2684 0.0120   1e-04
>       table$Table2
                        gene.index RP/Rsum FC:(class1/class2)    pfp P.value
AFFX-HUMRGE/M10098_3_at          6  8.1213             4.3141 0.0100   0e+00
AFFX-HUMRGE/M10098_5_at          4  9.2133             4.0339 0.0100   0e+00
AFFX-HUMRGE/M10098_M_at          5  9.8437             3.8488 0.0067   0e+00
D88270_at                      377 12.7578             3.5353 0.0200   2e-04
AFFX-M27830_5_at                14 14.3431             3.2518 0.0200   2e-04
> 
>       #using pvalue<0.05
>       topGene(RP.out,cutoff=0.05,method="pval",logged=TRUE,logbase=2,
+                    gene.names=golub.gnames[,3])
Table1: Genes called significant under class1 < class2 

Table2: Genes called significant under class1 > class2 

$Table1
                         gene.index RP/Rsum FC:(class1/class2)    pfp P.value
HG3494-HT3688_at                436  7.3165             0.2369 0.0200  0.0000
HG2724-HT2820_at                418  7.9323             0.2689 0.0100  0.0000
D87116_at                       346  8.2189             0.2605 0.0067  0.0000
HG987-HT987_at                  475  8.5880             0.3031 0.0100  0.0001
D88422_at                       378 10.2910             0.2684 0.0120  0.0001
D87433_at                       350 22.2528             0.3543 0.1550  0.0019
D26579_at                       141 25.2467             0.3970 0.1886  0.0026
D26308_at                       140 32.0381             0.5013 0.3512  0.0056
J03909_at                       496 35.9833             0.4730 0.4400  0.0079
D89052_at                       381 36.2952             0.4630 0.4030  0.0081
AFFX-HUMTFRR/M11507_3_at         13 37.0859             0.5117 0.3936  0.0087
HG3286-HT3463_at                431 40.5498             0.5563 0.4775  0.0115
AFFX-HUMTFRR/M11507_M_at         12 40.7818             0.5309 0.4485  0.0117
D49817_at                       215 41.3887             0.5280 0.4393  0.0123
D10495_at                        68 41.7633             0.4748 0.4207  0.0126
HG620-HT620_at                  470 42.8890             0.5305 0.4250  0.0136
D29643_at                       155 44.0282             0.5360 0.4271  0.0145
D83735_at                       303 44.1820             0.6354 0.4100  0.0148
D00726_at                        62 44.8851             0.5530 0.4058  0.0154
D43636_at                       198 46.7786             0.5724 0.4275  0.0171
D50915_at                       229 47.9356             0.6938 0.4457  0.0187
D30755_at                       160 49.3573             0.5308 0.4618  0.0203
D14874_at                       108 49.8597             0.5693 0.4522  0.0208
D50663_at                       219 51.8963             0.5953 0.4883  0.0234
D26129_at                       139 52.6567             0.5489 0.4892  0.0245
J03040_at                       483 55.4157             0.6112 0.5469  0.0284
D00761_at                        64 56.4930             0.6040 0.5567  0.0301
AF010193_at                      52 58.0885             0.6096 0.5768  0.0323
HG2810-HT2921_at                420 59.9292             0.6070 0.6069  0.0352
D13639_at                        85 60.9586             0.8286 0.6140  0.0368
D14811_at                       105 61.4964             0.6003 0.6061  0.0376
D16469_at                       115 61.6077             0.6106 0.5894  0.0377
J04027_at                       498 62.7902             0.5894 0.5991  0.0395
HG2788-HT2896_at                419 64.1737             0.5948 0.6162  0.0419
D67029_at                       266 64.2627             0.6410 0.6011  0.0421
D10202_at                        67 65.1456             0.5783 0.6083  0.0438
D87937_at                       374 66.0403             0.6749 0.6141  0.0454
D13641_at                        87 66.8993             0.6277 0.6189  0.0470
HG4662-HT5075_at                466 67.0424             0.5835 0.6064  0.0473
D50840_at                       222 68.4732             0.6578 0.6240  0.0499

$Table2
                        gene.index RP/Rsum FC:(class1/class2)    pfp P.value
AFFX-HUMRGE/M10098_3_at          6  8.1213             4.3141 0.0100  0.0000
AFFX-HUMRGE/M10098_5_at          4  9.2133             4.0339 0.0100  0.0000
AFFX-HUMRGE/M10098_M_at          5  9.8437             3.8488 0.0067  0.0000
D88270_at                      377 12.7578             3.5353 0.0200  0.0002
AFFX-M27830_5_at                14 14.3431             3.2518 0.0200  0.0002
D50918_at                      232 23.9021             2.4853 0.1050  0.0013
D11086_at                       74 26.8974             2.3623 0.1329  0.0019
HG1078-HT1078_at               389 31.8953             2.2554 0.2200  0.0035
D83776_at                      304 35.0233             2.1143 0.2722  0.0049
D86967_at                      329 35.8569             2.1269 0.2690  0.0054
HG4036-HT4306_at               451 38.2383             2.1038 0.3027  0.0067
D87076_at                      344 38.3284             2.0678 0.2775  0.0067
D86479_at                      323 38.9372             2.0832 0.2746  0.0071
D30742_at                      159 39.6655             2.0609 0.2707  0.0076
D86983_at                      337 41.5344             1.9518 0.2953  0.0089
D83780_at                      306 45.0103             1.9869 0.3662  0.0117
D42053_at                      193 45.0889             1.9259 0.3459  0.0118
AFFX-HSAC07/X00351_3_st         17 47.0776             1.9811 0.3839  0.0138
D87465_at                      369 48.1772             1.8293 0.3963  0.0151
D86970_at                      330 52.8865             1.8973 0.5055  0.0202
J03600_at                      491 54.3202             1.6096 0.5129  0.0215
D63486_at                      248 56.5033             1.8911 0.5523  0.0243
D38524_at                      182 56.5562             1.8116 0.5300  0.0244
HG1612-HT1612_at               394 56.6243             1.8526 0.5088  0.0244
D80005_at                      285 58.1699             1.6182 0.5276  0.0264
D78012_at                      267 61.4194             1.7997 0.6019  0.0313
D63880_at                      259 63.1282             1.7530 0.6219  0.0336
HG3039-HT3200_at               425 63.2380             1.7237 0.6021  0.0337
D87078_at                      345 66.1767             1.6936 0.6710  0.0389
D87438_at                      354 67.6645             1.7374 0.6907  0.0414
D43948_at                      202 68.8017             1.7289 0.6994  0.0434
AF003743_at                     44 69.1536             1.4669 0.6875  0.0440
HG4068-HT4338_at               452 69.3503             1.5081 0.6703  0.0442
D83032_at                      297 69.4787             1.7436 0.6535  0.0444
D29642_at                      154 69.7398             1.6527 0.6406  0.0448
D50930_at                      237 70.1365             1.7148 0.6308  0.0454
HG2825-HT2949_at               421 71.8410             1.6282 0.6568  0.0486

> 
>       #by selecting top 10 genes
> 
>       topGene(RP.out,num.gene=10,gene.names=golub.gnames[,3])
Table1: Genes called significant under class1 < class2 

Table2: Genes called significant under class1 > class2 

$Table1
                 gene.index RP/Rsum FC:(class1/class2)    pfp P.value
HG3494-HT3688_at        436  7.3165             0.2369 0.0200  0.0000
HG2724-HT2820_at        418  7.9323             0.2689 0.0100  0.0000
D87116_at               346  8.2189             0.2605 0.0067  0.0000
HG987-HT987_at          475  8.5880             0.3031 0.0100  0.0001
D88422_at               378 10.2910             0.2684 0.0120  0.0001
D87433_at               350 22.2528             0.3543 0.1550  0.0019
D26579_at               141 25.2467             0.3970 0.1886  0.0026
D26308_at               140 32.0381             0.5013 0.3512  0.0056
J03909_at               496 35.9833             0.4730 0.4400  0.0079
D89052_at               381 36.2952             0.4630 0.4030  0.0081

$Table2
                        gene.index RP/Rsum FC:(class1/class2)    pfp P.value
AFFX-HUMRGE/M10098_3_at          6  8.1213             4.3141 0.0100  0.0000
AFFX-HUMRGE/M10098_5_at          4  9.2133             4.0339 0.0100  0.0000
AFFX-HUMRGE/M10098_M_at          5  9.8437             3.8488 0.0067  0.0000
D88270_at                      377 12.7578             3.5353 0.0200  0.0002
AFFX-M27830_5_at                14 14.3431             3.2518 0.0200  0.0002
D50918_at                      232 23.9021             2.4853 0.1050  0.0013
D11086_at                       74 26.8974             2.3623 0.1329  0.0019
HG1078-HT1078_at               389 31.8953             2.2554 0.2200  0.0035
D83776_at                      304 35.0233             2.1143 0.2722  0.0049
D86967_at                      329 35.8569             2.1269 0.2690  0.0054

> 
> 
> 
> 
> 
> 
> dev.off()
null device 
          1 
>