HIBLUP has the function of calculating LD correlation (r) for pairwise SNPs based on genotype allele counts. The commands are as follows:
./hiblup --ld --bfile demo --window-bp 1e6 --threads 16 --out demo_ldm
Two files (*.info, *.bin) will be generated in the folder. Since the binary file (*.bin) cannot be opened directly, users can add a flag --write-txt
in the above commands to output a readable “.txt” file.
There are several options to set the window size:
--window-bp
: to specify the size of non-overlapped window (default 1Mb, i.e.,--window-bp 1000000
), in which the number of SNPs is not fixed;--window-num
: to specify a fixed number of SNPs in a window (e.g.,--window-num 500
), the size of window is not constant in this case;--window-geno
: to define all SNPs across entire genome as one window, note that it will take a long time and huge memory cost if there are large number of SNPs;--window-file
: to specify a text file in which the windows are pre-defined by users, see the file format here.