Add v4 CNVs

browser/help/topics/dataset-selection.md

@@ -56,3 +56,6 @@ The following subsets from previous versions are currently available, but access
 - _gnomAD SVs v2.1: Structural variant (SV) calls generated from a set of GS samples that largely overlaps those in gnomAD v2.1. This current SV release includes 10,847 unrelated genomes. See the [gnomAD-SV paper](https://broad.io/gnomad_sv) for details._
 - _gnomAD SVs v2.1 (non-neuro): Only samples from individuals who were not ascertained for having a neurological condition in a neurological case/control study._
 - _gnomAD SVs v2.1 (controls): Only samples from individuals who were not selected as a case in a case/control study of common disease._
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+The data selection drop-down also updates accompanying data such as the coverage plot, constraint statistics, regional constraint, and variant positional distribution plot.