highlight specific cells in a heatmap

[fersal]

Dear all,
I have gotten a heatmap with a data set that looks like the one below. The column “corrsing” in the data set contains the ratio of the correlation coefficients and their standard error, so by using this column I would like to get a heatmap in which all the coefficients with values <2 in the column "corrsig" being colored white or another color. eg the cells for A-D and C-D would be white. Any suggestion to get that?

var1   var2  corr   corrsig
 A     B     0.8    3.1
 A     C    -0.3    2.63
 A     D     0.25   1.5
 B     C    -0.75   2.9
 B     D     0.6    2.1
 C     D     0.1    0.82

Thanks in advance