I realize this is an older thread, just ran across it, but it seems still active. Any updates?
IMHO, if you do the testing then you have to tell your daughter the result very soon afterward - regardless of the result, and possibly before you discuss with your wife. The clinic will have records that you requested a test, and the results, which could inadvertently reach your daughter through countless paths you can't anticipate. Any family member could stumble onto your personal copy unless you destroy it. Your wife might use it against you in a fit of rage.
No matter what you do, if your daughter learns from anyone other than you, she'll always doubt you. You'll lose her trust.
She'll wonder about every event through her life, and your intentions at every milestone.
How does dealing with the worst case fallout compare to dealing with the anxiety of not knowing?
If you're consumed by anxiety... you may want (or need?) to discuss with a "mental health professional". Someone who can't reveal your concerns, but knows how to help you cope. I'll even speculate that this is the biggest, but not the only, issue causing your discomfort.
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