Often used as a QC parameter for cells in scRNA-seq data. The lower the expression level of housekeeping the genes, the more DNA contamination it suggests for the sample. In scRNAseq cancer data, this value is also used as a cutoff: e.g. a logTPM value >= 2.5 in order for a cell to be retained as HQ and with minimal DNA contamination. note: the list of housekeeping genes is taken from Normal_Markers$Housekeeping
expr_housekeeping(m, na.rm = T)matrix of expression values to test