CHAT (version 1.1)

getSegChr: Perform binned DNA segmentation by chromosome

Description

This function computes folded BAF and logR ratios for binned DNA segments for a given chromosome.

Usage

getSegChr(bb.chr = NULL, ll.chr = NULL, sam.col=5, control=TRUE, 
thr.hets=0.1, bin = 1000, data.type='copy',controlOne=0)

Arguments

bb.chr

numeric matrix, original B-allele frequency for a given chromosome for all samples.

ll.chr

numeric matrix, original logR ratio for a given chromosome for all samples.

sam.col

the index of the column in BAF or LRR files where the first sample starts

control

If TRUE, each tumor sample is paired with normal immediately after it. The columns of the data file is organized : sample_1, control_1, sample_2, control_2 .... If FALSE, each sample serves the control of itself.

thr.hets

lower threshold of calling homozygous markers. BAF<=thr.hets or="" baf="">=1-thr.hets are considered homozygous.

bin

integer, number of markers contained in each bin.

data.type

character string chosen from c('copy', 'log'). If 'copy', the value for LRR markers represent the copy number of SNPs. If 'log', the value is log2 based copy number intensity.

controlOne

default 0. If positive, must be an integer number indicating the index of one control sample in the sample list. This control will be used for all the samples.

Value

a matrix containing the following columns: chromosome, start position, end position, median LRR value, number of LRR markers, folded BAF value, number of germline heterozygous BAF markers, with row names being sample ID.

See Also

getSeg

Examples

library(CHAT)
data(A0SD.BAF)
data(A0SD.LRR)
CHR=8
chr8.baf=A0SD.BAF[which(A0SD.BAF[,2]==CHR),]
chr8.lrr=A0SD.LRR[which(A0SD.LRR[,2]==CHR),]
dd=getSegChr(chr8.baf,chr8.lrr)
print(dd[1:4,])