Jo-1 Antibody
An autoantibody tied to inflammatory muscle disease and a higher risk of associated lung involvement.
Consider this test if:
- Progressive muscle weakness with elevated creatine kinase or aldolase
- Unexplained shortness of breath or interstitial lung changes alongside muscle or joint symptoms
- Working up a positive ANA when an inflammatory myopathy is suspected
- Features of antisynthetase syndrome such as mechanic's hands, Raynaud phenomenon, and arthritis
- HSA/FSA eligible
- Results delivered to your dashboard · Reviewed by a real clinician
- Drawn at a CLIA/CAP-accredited lab near you ·
Pre-test considerations
No fasting required and timing does not affect the result. This is an antibody test, so recent corticosteroid or immunosuppressant treatment does not invalidate it, though it is most informative early in the workup.
Video consult with your Care Team
A 1:1 call to discuss your health.
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What this test is for
Jo-1 is one of the myositis-specific antibodies, directed against an enzyme (histidyl-tRNA synthetase) involved in protein synthesis. It is most strongly associated with polymyositis, where it appears in roughly a third of patients, and also shows up in dermatomyositis and in polymyositis overlap syndromes with scleroderma or lupus. A positive Jo-1 marks the antisynthetase syndrome, a pattern that links muscle inflammation with interstitial lung disease, arthritis, Raynaud phenomenon, and the thickened, cracked skin known as mechanic's hands. It is typically ordered when muscle weakness, elevated creatine kinase, unexplained shortness of breath, or a positive ANA points toward an inflammatory myopathy. A negative result does not exclude myositis, since many cases are driven by other autoantibodies.
What to expect
- 1 Book instantly
Click, book, done. Choose a convenient lab location near you. Transparent, up-front pricing.
- 2 Quick lab visit
Testing to fit your busy schedule, usually 15 minutes or less. Walk-in and appointments available.
- 3 Fast, dashboard-delivered results
Your results post straight to your dashboard as soon as the lab completes them.
- 4 Expert guidance
Included with Mito membership. A clinician reviews your results and your personalized action plan follows, with clear next steps.
Everything your health needs,
in one membership
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Every test at our cost
Members pay our cost on every test, with lab fees passed straight through. The full receipt is itemized, never padded.
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Continuous tracking, all in one place
Upload past labs and watch your trends over time. Every marker and visit lives in one longitudinal record, so all your care stays together.
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Year-round clinician support
Text anytime and get clinician-reviewed answers. When you want to go deeper, 1:1 consultations are available at affordable rates.
All for $9/month
Order any test or consult without joining. For $9/month, members unlock member prices, trend tracking, and year-round clinician guidance.
Mito Membership
$9 /mo
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Without membership
$0
pay as you go
At-cost pricing on labs, scans, and more
Priority turnaround on your results
On-demand clinician consults when you need guidance
Personalized action plans across supplements, exercise, nutrition, and sleep
AI health coaching to help you act on your results
Year-round medical support, with in-chat clinician escalation
All your health records in one personal vault, with trends and biological age tracking
Early access to new diagnostics and product releases
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Frequently asked questions
View all FAQsHow does pricing work?
Every test shows the member price next to the standard non-member price, so you can see what membership saves you. The member price is our cost — covering the lab and what it takes to run the service — never a profit on the test itself; Mito makes its money on the $9 membership, not on marking up your tests. Membership is $9/mo, and you still pay the lab’s order fee. Prices are itemized before you pay, with no hidden fees.
Where do I get tested?
Choose a partner lab (Quest, Labcorp, or BioReference) at checkout. If your cart spans multiple tests, we consolidate the whole order onto a single lab so you only make one visit.
Is this eligible for HSA/FSA?
Yes. This test is HSA/FSA eligible, and you can pay with your HSA/FSA card at checkout.
When will I get my results?
Your results post to your dashboard once your lab completes them, then a clinician reviews them and your full analysis and personalized action plan (with clear next steps) follow. Turnaround varies by test: specialty assays and at-home kits take longer, and each test shows its expected turnaround before you buy.
Do I need a doctor’s order?
No. Mito provides the lab order for you, so you can book and get tested without a separate doctor visit.
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