How to create DNA graphic?

[Vincent Rosati]

Helix 2

Helix 3

These show all of the techniques you will need.
However since the waves are repeating pattern, you could probably start with a straight path and apply Effect/Distort…/Zig-Zag, Smooth…

After you Object/Path/Outline Stroke the shaped path, you could offset a copy of the expanded shape and use Pathfinder/Subtract Back to create the lighter colored/front shapes to create the shading.

Vince

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