[BioC] HTqPCR plotting groups of interest

[Heidi Dvinge]

Hi Simon,

> If anyone can help, it would be great.
>
> I want to plot different groups of interest in HTqPCR using some of the
> plot functions, and I've played around with plotting different ways a
> number of times, and cant get the plot functions in HTqPCR to display what
> I want. I've a large number of groups, and dont want to plot everything
> every time (plotting everything works just fine after Heidi's help).
>
> #the plate6 CSV file links the sample ID to the group (Treatment) it
> belongs to#
>  >plate6=read.csv("PlateG6.csv", header=TRUE, as.is=TRUE)
>> head(plate6)
>   Sample Treatment
> 1    NTC       NTC
> 2    L29       LFY
> 3    M10       MMO
> 4    C30       CFY
> 5    S15       SFO
> 6    S28       SMY
>> group6=as.vector(t(plate6$Treatment))
>> sample6=as.vector(t(plate6$Sample))
>> raw6=readCtData(files="Chip6NTC.csv", format="BioMark", n.features=48,
>> n.data=48, samples=sample6)
>> g=featureNames(raw6)[1]
>> g
> [1] "TUB"
>> plotCtOverview(raw6, genes=g, col=rainbow(48), group=group6,
>> Legend=FALSE)
> #works fine, plots the first gene Tubulin nicely, however, now I want to
> compare my NTC group with my LFY group (listed in "Treatment" above)#

Do you just want the Ct values of NTC relative to LFY? In that case have a
look at the 'calibrator' parameter. As shown in the plotCtOverview
examples, setting calibrator="LFY" will show all Ct values for other
groups with LFY subtracted first.

> #I've tried the below to just plot one group, the "NTC" group, and it
> doesnt work (I'm not clear why, whatever is being plotted is not correct),
> #
> #not sure how to plot just two groups with this function (or three, or
> however many I want)#
>
>  >plotCtOverview(raw6, genes=g, col=rainbow(48), group=group6[1],
> legend=FALSE)
>
The problem here is that you're inputting an object with 6 columns, but
you're only providing link from 1 column to a group. On top of that,
plotCtOverview has no way of knowing which of the six columns you mean.

For plotting just some of your groups, you therefore need to subset your
qPCRset object. For example:

index


> thanks in advance
>
> Simon