The dataset is an R file called GC.RData. This file consists of two data
frames, called dd and metaDF. dd contains 159 numeric observations of
protein intensity (from a mass spectrometer) on 1080 blood serum samples
from 40 mice. The different protein peak intensities are arranged and
labelled by mass/charge ratio. Some of the observations are missing, and
are recorded as NA values. The object metaDF contains metadata for each
of the 1080 samples which consists of a record of mouse replicate
number, mouse genotype group, mass spectrometer chip number, the sample
location on the chip, and the scanning order of the mass spectrometer's
laser on the chip.