The estimated QTL effects, and the genotypes in the
phenotype x genotype plot, in the right-hand panels, are derived
following a single imputation to fill in missing data, and so are a
bit crude.
Note that the usual `height` and `width` options in
`chartOpts` are ignored here. Instead, you may provide
`pixelPerCell` (number of pixels per cell in the heat map),
`chrGap` (gaps between chr in heat map), `wright` (width
in pixels of right panels), and `hbot` (height in pixels of
each of the lower panels)