da33d70c10ddaae6c3290cb900d7d0cc2b6ee01b
hiram
  Tue Mar 17 13:57:24 2026 -0700
allow calculation of GC percent on the fly with code help from claude refs #35958

diff --git src/hg/htdocs/goldenPath/help/gcOnFly.html src/hg/htdocs/goldenPath/help/gcOnFly.html
new file mode 100644
index 00000000000..cec444859a8
--- /dev/null
+++ src/hg/htdocs/goldenPath/help/gcOnFly.html
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+<h2>Description</h2>
+<p>
+The GC percent track shows the percentage of G (guanine) and C (cytosine) bases
+in 5-base windows.  High GC content is typically associated with
+gene-rich areas.
+</p>
+<p>
+This track may be configured in a variety of ways to highlight different
+apsects of the displayed information. Click the
+&quot;Graph configuration help&quot;
+link for an explanation of the configuration options.
+
+<h2>Credits</h2>
+<p> The data and presentation of this graph were prepared by
+<a href="mailto:&#104;&#105;&#114;a&#109;&#64;&#115;&#111;&#101;
+.&#117;&#99;&#115;&#99;.&#101;&#100;u">Hiram Clawson</a>.
+</p>
+