# How to calculate combined expression of two genes

Hi,

I am trying to calculate the combined expression of two genes. I'm not entirely sure even where to begin with this. I have a list of cohorts that I obtained from a public database. I took the median RSEM normalized expression for each of the two genes and create a table that I will add below. I was just wondering how I can calculate the combined expression for these two genes? Let me know if you need any more detail.

``````test <- structure(list(cohort = c("ACC", "BLCA", "BRCA", "CESC", "CHOL",
"KICH", "KIPAN", "KIRC", "KIRP", "LGG", "LIHC", "LUAD", "LUSC",
"STAD", "STES", "TGCT", "THCA", "THYM", "UCEC", "UCS", "UVM"),
`gene A` = c(2.53523182291, 4.24028537986,
4.2961196377, 5.704706725705, 3.872673336325, 4.237031758135,
4.158417821, 6.031765535715, 5.310256918635, 4.885279662985,
3.74332062144, 6.33283859333, 6.07383185768, 5.22031447524,
5.34321592399, 4.5604234962, 3.2689938787, 3.03710103601,
5.94956061183, 6.19829180068, 4.31473277382, 4.18386758335,
4.668459860855, 5.08274090402, 3.07739683262, 4.00955320565,
3.933397760305, 4.22861092745, 5.26711626188, 5.28281785129,
4.50236485242, 5.60167869065, 6.67313176408, 3.311560724255,
1.95099089988, 3.53933318793), `gene B` = c(1.74549550948,
4.283760946765, 4.16740610241, 5.5645134556, 5.73067480081,
4.658244464035, 4.57945171425, 8.89577605866, 4.83403271751,
2.930135381415, 1.62832568781, 5.31851912397, 2.119853482145,
4.86034209697, 5.52799299981, 4.287668059045, 1.21801953053,
4.04097131218, 5.77614874252, 5.440736309, 5.93769984273,
4.51994441418, 5.01470489422, 2.51045562166, 3.91270734164,
4.30825164659, 4.30399502979, 4.61294809206, 5.69423389893,
5.43082049652, 6.74529471152, 4.43835939502, 8.31310826563,
5.257437091785, 4.23880214229, 1.84655825028)), row.names = c(NA,
-36L), class = "data.frame")
``````