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2022-07-18 生信技能树R语言小作业(中级)

2022-07-18 生信技能树R语言小作业(中级)

作者: 学习生信的小兔子 | 来源:发表于2022-07-18 16:26 被阅读0次

    题目来源 :http://www.bio-info-trainee.com/3750.html

    作业1

    请根据R包org.Hs.eg.db找到下面ensembl 基因ID 对应的基因名(symbol)

    ENSG00000000003.13
    ENSG00000000005.5
    ENSG00000000419.11
    ENSG00000000457.12
    ENSG00000000460.15
    ENSG00000000938.11
    
    library(org.Hs.eg.db)
    library(clusterProfiler)
    ensembl <- c("ENSG00000000003.13","ENSG00000000005.5","ENSG00000000419.11","ENSG00000000457.12","ENSG00000000460.15","ENSG00000000938.11")
    ensembl_sub <- str_sub(ensembl,1,15)
    gene_sym <- bitr(
      geneID = ensembl_sub,
      fromType = "ENSEMBL",
      toType = "SYMBOL",
      OrgDb = org.Hs.eg.db
    )
    >gene_sym
    ENSEMBL   SYMBOL
    1 ENSG00000000003   TSPAN6
    2 ENSG00000000005     TNMD
    3 ENSG00000000419     DPM1
    4 ENSG00000000457    SCYL3
    5 ENSG00000000460 C1orf112
    6 ENSG00000000938      FGR
    
    第二种方法
    g2s <- toTable(org.Hs.egSYMBOL);head(g2s)
    g2e <- toTable(org.Hs.egENSEMBL);head(g2e)
    ensembl <- tibble(
      ensembl=c("ENSG00000000003.13","ENSG00000000005.5","ENSG00000000419.11","ENSG00000000457.12","ENSG00000000460.15","ENSG00000000938.11")
    )
    
    for (i in 1:nrow(ensembl)){
      ensembl[i,]=str_sub(ensembl[i,],1,15)
      
    }
    tmp1 <- inner_join(
      ensembl,g2e,by="ensembl_id"
    )
    tmp2 <- inner_join(
      tmp1,g2s,by="gene_id"
    )
    
    tmp2
    # A tibble: 6 x 3
      ensembl_id      gene_id symbol  
      <chr>           <chr>   <chr>   
    1 ENSG00000000003 7105    TSPAN6  
    2 ENSG00000000005 64102   TNMD    
    3 ENSG00000000419 8813    DPM1    
    4 ENSG00000000457 57147   SCYL3   
    5 ENSG00000000460 55732   C1orf112
    6 ENSG00000000938 2268    FGR     
    
    

    作业2

    根据R包hgu133a.db找到下面探针对应的基因名(symbol)

    1053_at
    117_at
    121_at
    1255_g_at
    1316_at
    1320_at
    1405_i_at
    1431_at
    1438_at
    1487_at
    1494_f_at
    1598_g_at
    160020_at
    1729_at
    177_at
    
    library(hgu133a.db)
    columns(hgu133a.db)
    probe_id_c <- c("1053_at","117_at","121_at","1255_g_at","1316_at",
                    "1320_at","1405_i_at","1431_at","1438_at","1487_at",
                    "1494_f_at","1598_g_at","160020_at","1729_at","177_at")
    
    probe_id <- tibble(
      probe_id=probe_id_c
    )
    g2s <- toTable(hgu133aSYMBOL)
    tmp <- inner_join(
      probe_id,g2s,by="probe_id"
    )
    tmp
    # A tibble: 15 x 2
       probe_id  symbol
       <chr>     <chr> 
     1 1053_at   RFC2  
     2 117_at    HSPA6 
     3 121_at    PAX8  
     4 1255_g_at GUCA1A
     5 1316_at   THRA  
     6 1320_at   PTPN21
     7 1405_i_at CCL5  
     8 1431_at   CYP2E1
     9 1438_at   EPHB3 
    10 1487_at   ESRRA 
    11 1494_f_at CYP2A6
    12 1598_g_at GAS6  
    13 160020_at MMP14 
    14 1729_at   TRADD 
    15 177_at    PLD1  
    

    作业3

    找到R包CLL内置的数据集的表达矩阵里面的TP53基因的表达量,并且绘制在 progres.-stable分组的boxplot图

    library(CLL)
    data(sCLLex)
    exp <- exprs(sCLLex)
    pd <- pData(sCLLex)
    library(hgu95av2.db)
    g2s <- toTable(hgu95av2SYMBOL)
    g2s %>% 
      filter(symbol=="TP53")
    
    TP53_probe_id=g2s %>% 
      filter(symbol=="TP53") %>% 
      select(probe_id)
    TP53_probe_id=as.character(TP53_probe_id$probe_id)
    par(mfrow=c(1,3))
    boxplot(exp["1939_at",]~pd$Disease)
    boxplot(exp["1974_s_at",]~pd$Disease)
    boxplot(exp["31618_at",]~pd$Disease)
    

    作业4

    找到BRCA1基因在TCGA数据库的乳腺癌数据集(Breast Invasive Carcinoma (TCGA, PanCancer Atlas))的表达情况
    参考:找到TP53基因在TCGA数据库的肝癌数据集的表达情况 - 简书 (jianshu.com)

    作业5

    找到TP53基因在TCGA数据库的乳腺癌数据集的表达量分组看其是否影响生存
    参考:找到TP53基因在TCGA数据库的乳腺癌数据集的表达量分组看其是否影响生存 - 简书 (jianshu.com)

    作业6

    下载数据集GSE17215的表达矩阵并且提取下面的基因画热图

    ACTR3B ANLN BAG1 BCL2 BIRC5 BLVRA CCNB1 CCNE1 CDC20 CDC6 CDCA1 CDH3 CENPF CEP55 CXXC5 EGFR ERBB2 ESR1 EXO1 FGFR4 FOXA1 FOXC1 GPR160 GRB7 KIF2C KNTC2 KRT14 KRT17 KRT5 MAPT MDM2 MELK MIA MKI67 MLPH MMP11 MYBL2 MYC NAT1 ORC6L PGR PHGDH PTTG1 RRM2 SFRP1 SLC39A6 TMEM45B TYMS UBE2C UBE2T

    load("D:/genetic_r/R-practise/GSE17215_eSet.Rdata")
    
    gset1 <- gset[[1]] 
    exp <- exprs(gset1)
    exp <- as.data.frame(exp)
    pd <- pData(gset1)
    library(hgu133a.db)
    ids <- toTable(hgu133aSYMBOL)
    exp=exp %>% 
      mutate(probe_id=rownames(exp))
    exp=exp %>% 
      inner_join(ids,by="probe_id")
    exp=exp %>% 
      select(-probe_id)
    exp=exp %>% 
      select(symbol,everything())
    exp=exp %>%  
      mutate(rowMean=rowMeans(.[,-1])) %>% 
      arrange(desc(rowMean)) %>% 
      distinct(symbol,.keep_all = T) %>% 
      select(-rowMean) %>% 
      column_to_rownames("symbol")
    ng='ACTR3B ANLN BAG1 BCL2 BIRC5 BLVRA CCNB1 CCNE1 CDC20 CDC6 CDCA1 CDH3 CENPF CEP55 CXXC5 EGFR ERBB2 ESR1 EXO1 FGFR4 FOXA1 FOXC1 GPR160 GRB7 KIF2C KNTC2 KRT14 KRT17 KRT5 MAPT MDM2 MELK MIA MKI67 MLPH MMP11 MYBL2 MYC NAT1 ORC6L PGR PHGDH PTTG1 RRM2 SFRP1 SLC39A6 TMEM45B TYMS UBE2C UBE2T'
    ng=str_split(ng,' ')
    ng=unlist(ng)
    table(ng%in%rownames(exp))
    ng=ng[ng%in%rownames(exp)]
    dat=exp[ng%in%rownames(exp),]
    # 清洗掉不存在的ng,注意这一步存在排序(连同下一步理解)
    ng=ng[ng %in%  rownames(exp)]
    
    dat=exp[ng,]
    
    # 画图
    dat=log2(dat)
    pheatmap::pheatmap(dat,scale = 'row')
    

    作业7

    下载数据集GSE24673的表达矩阵计算样本的相关性并且绘制热图,需要标记上样本分组信息

    rm(list = ls())  
    options(stringsAsFactors = F)
    gset <- getGEO( 'GSE24673', getGPL = F )
    library(GEOquery)
    gset <- gset [[1]]
    exp <- exprs(gset)
    pd <- pData(gset)
    exp <- as.data.frame(exp)
    group_list=c('rbc','rbc','rbc',
                 'rbn','rbn','rbn',
                 'rbc','rbc','rbc',
                 'normal','normal')
    exp[1:4,1:4]
    #相关性分析
    M=cor(exp)
    pheatmap::pheatmap(M)
    
    tmp=data.frame(g=group_list)
    rownames(tmp) <- colnames(M)
    pheatmap::pheatmap(M,annotation_col = tmp)
    

    作业8

    找到 GPL6244 platform of Affymetrix Human Gene 1.0 ST Array 对应的R的bioconductor注释包,并且安装它!
    可在此搜索
    用R获取芯片探针与基因的对应关系三部曲-bioconductor | 生信菜鸟团 (bio-info-trainee.com)

    platformMap <- data.table::fread("resource/platformMap.txt",data.table = F)
    [1] "hugene10sttranscriptcluster.db" #可获得对应的注释包
    ## 平台的名称如何知道?
    index <- "GPL6244"
    ## 数据储存在bioc_package这一列中
    paste0(platformMap$bioc_package[grep(index,platformMap$gpl)],".db")
    
    ## 安装R包,可以直接安装,这里用了判断
    if(!requireNamespace("hugene10sttranscriptcluster.db")){
      options(BioC_mirror="https://mirrors.ustc.edu.cn/bioc/")
      BiocManager::install("hugene10sttranscriptcluster.db",update = F,ask = F)
    } 
    
    ## 加载R包
    library(hugene10sttranscriptcluster.db)
    

    作业9

    下载数据集GSE42872的表达矩阵,并且分别挑选出 所有样本的(平均表达量/sd/mad/)最大的探针,并且找到它们对应的基因。

    rm(list = ls())  
    options(stringsAsFactors = F)
    gset <- getGEO( 'GSE42872', getGPL = F )
    library(GEOquery)
    gset <- gset [[1]]
    exp <- exprs(gset)
    pd <- pData(gset)
    exp <- as.data.frame(exp)
    #由平台 "GPL6244"可得出注释包为hugene10sttranscriptcluster.db
    #加载注释包
    library(hugene10sttranscriptcluster.db)
    ids <- toTable(hugene10sttranscriptclusterSYMBOL)
    exp=exp %>% 
      rownames_to_column("probe_id")
    exp <- inner_join(exp,ids,by="probe_id")
    exp=exp %>% 
      select(probe_id,symbol,everything())
    
    #平均表达量
    exp=exp %>%
      mutate(rowmean=rowMeans(.[,-c(1,2)]))
    #找最大
    exp %>% 
      arrange(-rowmean) %>% 
      head(1)
    #7953385  GAPDH
    #mad
    exp=exp %>% 
      mutate(md=apply(exp[,3:8],1,median))
    exp %>% 
      arrange(-md) %>% 
      head(1)
    #7953385  GAPDH
    #sd
    exp=exp %>% 
      mutate(sd=apply(exp[,3:8],1,sd))
    exp %>% 
      arrange(-sd) %>% 
      head(1)
    #8133876  CD36
    

    作业10

    下载数据集GSE42872的表达矩阵,并且根据分组使用limma做差异分析,得到差异结果矩阵

    rm(list = ls())  
    options(stringsAsFactors = F)
    gset <- getGEO( 'GSE42872', getGPL = F )
    library(GEOquery)
    gset <- gset [[1]]
    exp <- exprs(gset)
    exp <- as.data.frame(exp)
    pd <- pData(gset)
    
    
    group_list=character(6)
    for (i in 1:nrow(pd)){
      group_list[i]=strsplit(pd$title[i],' ')[[1]][4]
    }
    
    exprSet=exp
    # 用limma包做差异表达分析
    #差异分析重点在于做好表达矩阵和分组信息,具体原理可以不用理解
    suppressMessages(library(limma)) 
    design <- model.matrix(~0+factor(group_list))
    colnames(design)=levels(factor(group_list))
    rownames(design)=colnames(exprSet)
    design
    contrast.matrix<-makeContrasts(paste0(unique(group_list),collapse = "-"),levels = design)
    contrast.matrix 
    ##step1
    fit <- lmFit(exprSet,design)
    ##step2
    fit2 <- contrasts.fit(fit, contrast.matrix) ##这一步很重要,大家可以自行看看效果
    fit2 <- eBayes(fit2)  ## default no trend !!!
    ##eBayes() with trend=TRUE
    ##step3
    tempOutput = topTable(fit2, coef=1, n=Inf)
    nrDEG = na.omit(tempOutput) 
    #write.csv(nrDEG2,"limma_notrend.results.csv",quote = F)
    head(nrDEG)
    

    参考:盘一盘 生信技能树R语言小作业(中级) - 简书 (jianshu.com)

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