“Lesson 02&03 for Plotting in R for Biologists”

mark

Lesson02主要讲了如何从Excel导入数据以及如何从UCSC、ENSEMBL和RENCODE上下载数据,因此我就将Lesson02并入Lesson03一起讲了。

从ECXEl中导入数据

数据来源于文献 “Gene expression profiling of breast cell lines identifies potential new basal markers”的补充数据集Supplementary Table 1。将之下载到工作目录区。数据读取的话只需要用read.csv()即可,指定sepgtfbed文件都可以通过read.csv()读取。即使是没有后缀的文件,只要知道其分隔符,就可以通过设置sep来读取数据。

my_data <- read.csv("micro_array_results_table1.txt", sep = '\t', header = TRUE)
head(my_data[,c(1:6)])
##   Probe.Set.ID Gene.Symbol Type  X184B5 BrCa.MZ.01   BT.20
## 1    1007_s_at        DDR1 gene 1113.91     815.53 1564.76
## 2      1053_at        RFC2 gene  159.02     253.24  320.22
## 3       117_at       HSPA6 gene   60.76      33.91   26.39
## 4       121_at        PAX8 gene  197.76     121.33  122.81
## 5    1255_g_at      GUCA1A gene    6.73       7.88    6.28
## 6      1294_at       UBE1L gene  118.82      57.24  432.24

试试读取gtf文件

Brassica_gtf <- read.csv("E:/Brassica napus database/Brassica_napus.annotation_v5.gtf", sep = "\t", header = FALSE)
head(Brassica_gtf)
##       V1     V2   V3   V4   V5   V6 V7 V8                           V9
## 1 chrA01 GazeA2 exon  831 1437 7.80  +  . transcript_id BnaA01g00010D;
## 2 chrA01 GazeA2  CDS 1070 1345    .  +  0 transcript_id BnaA01g00010D;
## 3 chrA01 GazeA2 exon 1487 2124 2.15  -  . transcript_id BnaA01g00020D;
## 4 chrA01 GazeA2 exon 2256 2436 3.19  -  . transcript_id BnaA01g00020D;
## 5 chrA01 GazeA2  CDS 1645 2124    .  -  0 transcript_id BnaA01g00020D;
## 6 chrA01 GazeA2  CDS 2256 2282    .  -  0 transcript_id BnaA01g00020D;

其他格式文件我这里就不试了,有兴趣的话可以自己去尝试。

数据探索

library(tidyverse)
#读取数据
my_data <- read.csv("Encode_HMM_data.txt", sep = "\t", header = FALSE)
dim(my_data)
## [1] 571339      9
head(my_data[, c(1:6)])
##     V1    V2    V3                V4 V5 V6
## 1 chr1 10000 10600 15_Repetitive/CNV  0  .
## 2 chr1 10600 11137 13_Heterochrom/lo  0  .
## 3 chr1 11137 11737       8_Insulator  0  .
## 4 chr1 11737 11937       11_Weak_Txn  0  .
## 5 chr1 11937 12137   7_Weak_Enhancer  0  .
## 6 chr1 12137 14537       11_Weak_Txn  0  .

对数据部分列进行重命名

names(my_data)[1:4] <- c("chrom", "start", "stop", "type")

可视化

先初步看一下不同染色体上的type类型

ggplot(my_data, aes(x=chrom, fill=type))+geom_bar()

mark

从这个图中可以看到还有很多缺陷

  • 染色体顺序错乱,前缀chr在坐标轴上排列乱
  • 类型太多了,我们只需要可视化我们感兴趣的type
  • 类型的名字乱

这几个问题将在Lesson04解决

SessionInfo()

sessionInfo()
## R version 3.4.3 (2017-11-30)
## Platform: x86_64-w64-mingw32/x64 (64-bit)
## Running under: Windows 10 x64 (build 16299)
## 
## Matrix products: default
## 
## locale:
## [1] LC_COLLATE=Chinese (Simplified)_China.936 
## [2] LC_CTYPE=Chinese (Simplified)_China.936   
## [3] LC_MONETARY=Chinese (Simplified)_China.936
## [4] LC_NUMERIC=C                              
## [5] LC_TIME=Chinese (Simplified)_China.936    
## 
## attached base packages:
## [1] stats     graphics  grDevices utils     datasets  methods   base     
## 
## other attached packages:
## [1] forcats_0.2.0      stringr_1.2.0      dplyr_0.7.4       
## [4] purrr_0.2.4        readr_1.1.1        tidyr_0.7.2       
## [7] tibble_1.4.2       ggplot2_2.2.1.9000 tidyverse_1.2.1   
## 
## loaded via a namespace (and not attached):
##  [1] Rcpp_0.12.15      cellranger_1.1.0  pillar_1.1.0     
##  [4] compiler_3.4.3    plyr_1.8.4        bindr_0.1        
##  [7] tools_3.4.3       digest_0.6.14     lubridate_1.7.1  
## [10] jsonlite_1.5      evaluate_0.10.1   nlme_3.1-131     
## [13] gtable_0.2.0      lattice_0.20-35   pkgconfig_2.0.1  
## [16] rlang_0.1.6       psych_1.7.8       cli_1.0.0        
## [19] rstudioapi_0.7    yaml_2.1.16       parallel_3.4.3   
## [22] haven_1.1.1       bindrcpp_0.2      xml2_1.2.0       
## [25] httr_1.3.1        knitr_1.18        hms_0.4.1        
## [28] rprojroot_1.3-2   grid_3.4.3        glue_1.2.0       
## [31] R6_2.2.2          readxl_1.0.0      foreign_0.8-69   
## [34] rmarkdown_1.8     modelr_0.1.1      reshape2_1.4.3   
## [37] magrittr_1.5      backports_1.1.2   scales_0.5.0.9000
## [40] htmltools_0.3.6   rvest_0.3.2       assertthat_0.2.0 
## [43] mnormt_1.5-5      colorspace_1.3-2  labeling_0.3     
## [46] stringi_1.1.6     lazyeval_0.2.1    munsell_0.4.3    
## [49] broom_0.4.3       crayon_1.3.4
Researcher

I am a PhD student of Crop Genetics and Breeding at the Zhejiang University Crop Science Lab. My research interests covers a range of issues:Population Genetics Evolution and Ecotype Divergence Analysis of Oilseed Rape, Genome-wide Association Study (GWAS) of Agronomic Traits.

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