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The Edit sequence submenu is available in the Actions main menu and in the Sequence View context menu. Also you can use the corresponding shortuts.
When you press the Ctrl+I shortcut or select the Insert subsequence item context menu item the following dialog is opened:
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In case a subsequence has been selected, the Replace subsequence is available from the context menu or by the Ctrl+R shortcut. The dialog opened in this case is similar to the dialog described above, except it already contains the sequence to be edited an doesn’t allow to input the start position.
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