1. 程式人生 > >一個函數實現基因內具有多種突變類型的熱圖的繪制

一個函數實現基因內具有多種突變類型的熱圖的繪制

TP 必須 長度 部分 point 顯示效果 heatmap points bar

技術分享圖片
技術分享圖片

??我們平常多見的基因突變熱圖是一個基因一個格子,一種突變類型,但實際上在同一個病人中,同一個基因往往具有多種突變類型,因此傳統的熱圖繪制工具並不能滿足我們繪圖的需要。應研究需要,本人自己寫了一個熱圖繪制函數,內部調用image 進行熱圖的繪制, barplot進行直方圖繪制, 用data.table進行數據處理。對於一個基因內多種突變類型如何表現出來的問題, 這個函數先采用image將初步的熱圖繪制出來,再使用points,以方塊形式將第二種突變,第三種突變依次添加, 在添加的同時方塊位置稍為移動並且伴隨著大小的略微縮小,以實現更好的顯示效果,最多能在一個熱圖格子上表示四種突變。
??函數如下, 需要安裝並加載data.table 1.10.4, 加載RColorBrewer

my_heatmap <- function(vr, pal = c("#F2F2F2",colorRampPalette(c("blue", "white", "red"))(5)[c(1,2)],"#F2F2F2",colorRampPalette(c("blue", "white", "red"))(5)[c(4,5)],brewer.pal(n = 8, name ="Accent")[c(1,4,6,8,2,3,5,7)],"#E31A1C","#6A3D9A"),type = c("DEL","LOSS","NEUTRAL","GAIN","AMPL","nonsynonymous SNV","synonymous SNV","intronic","stopgain","nonframeshift deletion","splicing", "frameshift deletion","UTR3","frameshift insertion","UTR5"),
                       order_gene = T, order_patient = T, hist_plot = T, legend_dist = 0.4, col_text_cex = 1, sub_gene= NULL,heatmap_mar = c(5,17,1,2), heatmap_oma=c(0.2,0.2,0.2,0.2),heatmap_mex=0.5, legend_mar = c(1,0,4,1),xlab_adj=1, order_omit=c("NoMut","NEUTRAL"))
{
  if((length(pal) - length(type)) !=1 ){stop("Pal must be one longer than type, because first one pal is col for no mutation")}
  if(!is.null(sub_gene)){
    pal_dt <- data.table(pal, type=c("NoMut",type))
    vr <- vr[Gene %in% sub_gene,]
    type <- pal_dt[type %in% unique(vr$Type),type]
    pal <- c(pal[1],pal_dt[type, on="type"][,pal])
  }else{
    pal_dt <- data.table(pal, type=c("NoMut",type))
    type <- pal_dt[type %in% unique(vr$Type),type]
    pal <- c(pal[1],pal_dt[type, on="type"][,pal])
  }
  dt <- unique(vr[,.(Gene,Type,Patient)])
  if(is.null(type)){type <- data.table(table(vr$Type))[order(-N),V1]}
  dt$Type <- factor(dt$Type, levels = type)
  gene <- dt[!Type %in% order_omit,.(N=length(unique(Patient))),by=Gene][order(N),Gene]
  dt$Gene <- factor(dt$Gene, levels = gene)
  patient <- data.table(table(vr[!Type %in% order_omit,]$Patient))[order(-N),V1]
  dt$Patient <- factor(dt$Patient, levels = c(patient, setdiff(unique(dt$Patient),patient)))
  
  
  if(order_gene & !order_patient){setkey(dt, "Gene")}
  if(!order_gene & order_patient){setkey(dt, "Patient")}
  if(order_gene & order_patient){setkey(dt, "Gene","Patient","Type")}
  
  n <- length(unique(dt$Type))
  
  dt$Gene_Patients <- paste(dt$Gene, dt$Patient)
  dt_inf <- dt[,.N,by=.(Gene, Patient)]
  max_mut_num <- max(dt_inf$N)
  dt[,Mut_num:=seq_len(.N),by=.(Patient,Gene)]

  #main plot, heatmap using first mutation type
  dt1 <- copy(dt)
  dt1[Mut_num !=1, Type:=NA]
  dc <- data.frame(dcast(dt1, Patient ~ Gene, value.var = "Type", fun.aggregate = function(x)(x[!is.na(x)][1])))
  rownames(dc)<- dc[,1]
  data_matrix<-data.matrix(dc[,-1])
  data_matrix[is.na(data_matrix)] <- 0
  pal=pal
  breaks<-seq(-1,10,1)
  if(!hist_plot){
    layout(matrix(data=c(1,2), nrow=1, ncol=2), widths=c(8,2), heights=c(1,1))
    par(mar=heatmap_mar, oma=heatmap_oma, mex=heatmap_mex)
  }else if(hist_plot){
    layout(matrix(c(2,4,1,3),2,2,byrow=TRUE), widths=c(3,1), 
           heights=c(1,3), TRUE)
    par(mar=heatmap_mar)
  }
  
  
  image(x=1:nrow(data_matrix),y=1:ncol(data_matrix),
        z=data_matrix,xlab="",ylab="",breaks=breaks,
        col=pal[1:11],axes=FALSE)
  
  
  #sub plot, points using other mutation type
  add_plot <- function(dt, i){
    dt1 <- copy(dt)
    dt1[Mut_num != i, Type:=NA]
    dc <- data.frame(dcast(dt1, Patient ~ Gene, value.var = "Type", fun.aggregate = function(x){ifelse(length(x) >1,x[!is.na(x)][1],factor(NA))}))
    rownames(dc)<- dc[,1]
    data_matrix <- data.matrix(dc[,-1])
    xy <- which(data_matrix !=0, arr.ind = T)
    #apply(xy, 1, function(x)points(x[1], x[2],pch=15, cex=2.5 -0.5*i, col=pal[data_matrix[x[1],x[2]]+1]))
    apply(xy, 1, function(x)points(x[1]-0.6+i*0.25, x[2],pch=15, cex=1.2 - i*0.08, col=pal[data_matrix[x[1],x[2]]+1]))
  }
  
  ploti <- data.frame(i=2:max_mut_num)
  apply(ploti, 1, function(i){print(add_plot(dt, i))})
  
  text(x=1:nrow(data_matrix)+0.1, y=par("usr")[1] - xlab_adj, 
       srt = 90, adj = 0.5, labels = rownames(data_matrix), 
       xpd = TRUE, cex=col_text_cex)
  axis(2,at=1:ncol(data_matrix),labels=colnames(data_matrix),
       col="white",las=1, cex.lab=0.1)
  abline(h=c(1:ncol(data_matrix))+0.5,v=c(1:nrow(data_matrix))+0.5,
         col="white",lwd=2,xpd=F)
  #title("Correlation between genes",line=8,adj=0)
  
  if(hist_plot){
    #bar plot
    par(mar=c(0,2+0.5,3,heatmap_mar[4]-0.9))
    patient_dt <- dt[,.N,by=.(Patient,Type)]
    mt <- data.frame(dcast(patient_dt, Type ~ Patient, value.var = "N"))
    data_matrix <- data.matrix(mt[,-1])
    rownames(data_matrix) <- mt[,1]
    tryCatch(data_matrix <- data_matrix[setdiff(type, order_omit), patient], error = function(e){print("type argument or your patient name format(include "-" and so on )")})
    data_matrix[is.na(data_matrix)] <- 0
    omit_idx <- NULL
    for(i in order_omit){omit_idx <- c(omit_idx,1+which(type == i))}
    barplot(data_matrix, col=pal[-c(1,omit_idx)],space=0,border = "white",axes=T,xlab="",ann=F, xaxt="n")
    
    par(mar=c( heatmap_mar[1]-2 , 0.8, heatmap_mar[3]+2.2, 3),las=1)
    gene_dt <- dt[,.N,by=.(Gene,Type)]
    mt <- data.frame(dcast(gene_dt, Type ~ Gene, value.var = "N"))
    data_matrix <- data.matrix(mt[,-1])
    rownames(data_matrix) <- mt[,1]
    gene <- gsub("ATM,", "ATM.", gene)
    tryCatch(data_matrix <- data_matrix[setdiff(type, order_omit), gene], error = function(e){print("type argument or check your gene name format(please not include "-" and so on)")})
    data_matrix[is.na(data_matrix)] <- 0
    barplot(data_matrix, col=pal[-c(1,omit_idx)],space=0,border = "white",axes=T,xlab="", ann=F, horiz = T, yaxt="n")
    
  }
  
  #add legend   
  par(mar=legend_mar)
  plot(3, 8,  axes=F, ann=F, type="n")
  ploti <- data.frame(i=1:length(type))
  if(!hist_plot){
    tmp <- apply(ploti, 1, function(i){print(points(2, 10+(length(type)-i)*legend_dist, pch=15, cex=2, col=pal[i+1]))})
    tmp <- apply(ploti, 1, function(i){print(text(3, 10+(length(type)-i)*legend_dist, labels = type[i],pch=15, cex=1, col="black"))})
  }
  if(hist_plot){
    tmp <- apply(ploti, 1, function(i){print(points(2, 5+(length(type)-i)*legend_dist, pch=15, cex=0.9, col=pal[i+1]))})
    tmp <- apply(ploti, 1, function(i){print(text(2.8, 5+(length(type)-i)*legend_dist, labels = type[i],pch=15, cex=0.9, col="black"))})  
  }
  
}

描述
??繪制一個基因可以同時顯示多種突變類型的熱圖,輸入三列的data table數據框, 列名分別是Gene,Type, 和 Patient,輸出熱圖, 還可以在熱圖上方和右方添加突變的直方圖。
用法:

my_heatmap(vr, pal = c("#F2F2F2",colorRampPalette(c("blue", "white", "red"))(5)[c(1,2)],"#F2F2F2",colorRampPalette(c("blue", "white", "red"))(5)[c(4,5)],brewer.pal(n = 8, name ="Accent")[c(1,4,6,8,2,3,5,7)],"#E31A1C","#6A3D9A"),type = c("DEL","LOSS","NEUTRAL","GAIN","AMPL","nonsynonymous SNV","synonymous SNV","intronic","stopgain","nonframeshift deletion","splicing", "frameshift deletion","UTR3","frameshift insertion","UTR5"),order_gene = T, order_patient = T, hist_plot = T, legend_dist = 0.4, col_text_cex = 1,xlab_adj=1, sub_gene= NULL,heatmap_mar = c(5,17,1,2), heatmap_oma=c(0.2,0.2,0.2,0.2),heatmap_mex=0.5, legend_mar = c(1,0,4,1), order_omit=c("NEUTRAL"))

參數:
vr: 含有變異數據的數據框,共三列,列名分別是Gene, Type, Patient;
pal: 色板,向量,需要根據數據框中突變類型的數量進行自定義,需要比突變類型多一種顏色作為背景色,背景色放在第一位;
type:色板相對應的突變類型,向量,type必須等於或者多於數據中所出現的所有類型;默認使用拷貝數的四種突變類型加上拷貝數中性再加上annovar中所有突變類型;自定義設置時長度要比色板少1;
order_gene: 默認T, 對基因按照突變的病人數目進行排序;
order_patient:默認T,對病人按照突變的基因數目進行排序;
hist_plot:默認T,在上方和右方加上對應的直方圖;
legend_dist:默認0.4,調整圖例之間相互的距離,一般需要自行調整;
col_text_cex:調整病人名稱的大小,默認1;
xlab_adj:調整病人名稱與熱圖之間的距離;
sub_gene:只選擇部分基因進行畫圖,需要給基因名的向量,並且基因需要在數據中存在,默認NULL
heatmap_mar:mar參數,調整熱圖前後左右的邊緣長度,默認c(5,17,1,2)
heatmap_oma:oma參數,調整熱圖前後左右的外邊緣長度,默認c(0.2,0.2,0.2,0.2)
mex:調整熱圖的mex參數,用於描繪繪圖邊緣的坐標,默認0.5
legend_mar:legend的mar參數,調整圖例的位置,默認c(1,0,4,1)
order_omit:排序時忽略的變異類型,這些突變類型在直方圖中也會被過濾,默認c("NEUTRAL"),如果不存在"NEUTRAL"這種突變類型,也可以保持默認參數。

細節

  • 運行前需要加載data.table1.10.4, RColorBrewer;
  • 如果要繪制帶有直方圖的熱圖,因為圖片尺寸過大,因此要使用pdf函數並要給足夠大的寬度和長度;
  • 默認使用的是annovar註釋的突變類型;
  • 因為繪制時影響熱圖和直方圖對齊的因素太多,很難通過調節相應的mar,mex,oma參數達到較好的效果,因此推薦快速畫出個大概後,再使用inkscape或adobe進行排版對齊
  • 如果熱圖中突變類型的點過小,可以減小pdf文件的寬度和長度。

使用例子

#without hist plot
pdf("~/project/PE/fromws02/PE/cnv_plot/heatmap_cnv_mut.pdf", height=12, width = 12)
my_heatmap(vr, heatmap_mar = c(17,17,1,2),hist_plot = F, legend_dist=0.1, xlab_adj = 1.2, order_patient = T, order_gene = T)
dev.off()

#with hist plot
pdf("~/project/PE/fromws02/PE/cnv_plot/heatmap_hist_cnv_mut.pdf", height=12, width = 12)
my_heatmap(vr, heatmap_mar = c(17,7,1,2),hist_plot = T, legend_dist=0.3, xlab_adj = 1.2, order_patient = T, order_gene = T)
dev.off()

#only a few gene
pdf("~/project/PE/fromws02/PE/cnv_plot/Assoc_CN1.pdf", height=2,width = 14)
my_heatmap(vr, heatmap_mar = c(7,17,1,2), sub_gene = c("CDKN2A", "GNAQ", "NOTCH1", "RB1", "SMAD4", "ABL1"),hist_plot = F,legend_dist=0.2, xlab_adj = 0.9, order_omit = "NEUTRAL")
dev.off()

一個函數實現基因內具有多種突變類型的熱圖的繪制