seqnames = &quot;chr1&quot;, ranges = IRanges(start = 1:4, width = 3))
gr2 &lt;- GRanges(seqnames = &quot;chr2&quot;, ranges = IRanges(start = 1:4, width = 3))
gL &lt;- GRangesList(gr1 = gr1, gr2 = gr2)
gL</code></pre>
<pre><code>## GRangesList object of length 2:
## $gr1 
## GRanges object with 4 ranges and 0 metadata columns:
##       seqnames    ranges strand
##          &lt;Rle&gt; &lt;IRanges&gt;  &lt;Rle&gt;
##   [1]     chr1    [1, 3]      *
##   [2]     chr1    [2, 4]      *
##   [3]     chr1    [3,