What's this test for?

This test is ideal if you or a loved one has been diagnosed with, or is being evaluated for, B-cell acute lymphoblastic leukemia (ALL) and needs more detail about the genetic makeup of the abnormal cells. It looks for a specific gene rearrangement (CRLF2) that can affect how the leukemia behaves and how it may respond to treatment. This test is typically used alongside other bone marrow or blood work already in progress, not as a general first-line health check.

What happens after I get my results?

Your results will show up in your account with a plain-language explanation of whether the CRLF2 rearrangement was found and what a normal versus abnormal finding means. Because this is a specialized genetic test tied to an existing leukemia workup, next steps usually involve sharing the report with your treatment team so it can be factored into the overall picture rather than acting on it alone. You can download the full lab report from your account at any time, and if repeat testing is ever needed to track changes over time, you'll be able to compare results using the trends feature.

Who should consider this test?

This test is generally considered for people already diagnosed with B-cell ALL, especially children, teens, and young adults, since CRLF2 rearrangements show up more often in these groups. It's also useful for cases where standard chromosome testing didn't fully explain the leukemia's genetic profile. It is not intended as a routine screening test for people without a leukemia diagnosis or strong clinical suspicion of one.

What symptoms indicate I may need this test?

On its own, a CRLF2 rearrangement doesn't cause specific symptoms — it's the underlying leukemia that does. Signs that may lead to this kind of testing include unexplained fatigue, frequent infections, easy bruising or bleeding, bone or joint pain, and swollen lymph nodes. If these symptoms are already being investigated with blood counts or a bone marrow biopsy, this FISH test can add helpful genetic detail to that workup.

When will I get my results?

Results for this specialized FISH test typically take about 7 days to process, since it involves detailed genetic analysis of the sample. You'll receive a notification as soon as your report is ready in your account. This turnaround can vary slightly depending on sample quality, so check your account for the most current status.

What is a CRLF2 gene rearrangement and why does it matter?

CRLF2 is a gene that helps control how certain white blood cells grow. When it becomes rearranged — often fusing with genes on the X or Y chromosome or with an immunoglobulin gene — it can send growth signals that go into overdrive, which is linked to some cases of B-cell ALL. Identifying this rearrangement helps characterize the leukemia more precisely, which can be useful for understanding disease behavior.

What does a positive (rearrangement detected) result mean?

A positive result means the FISH test found a break and rearrangement in the CRLF2 gene region, which is associated with a subtype of B-cell ALL. This finding adds detail to the overall leukemia diagnosis and is typically considered together with other test results rather than by itself. It does not change how the sample was collected or processed — it simply confirms the genetic pattern was present.

What does a negative (no rearrangement detected) result mean?

A negative result means the FISH probe did not detect a break-apart pattern in the CRLF2 region in the cells examined. This suggests that this particular genetic change is not driving the leukemia in that sample, which can help rule out one subtype while other testing continues to build the full picture. It's one piece of a larger diagnostic puzzle, not a standalone answer.

How often should I retest?

This is not a test you'd repeat on a regular schedule like routine bloodwork — it's typically done once during diagnosis or workup unless there's a specific clinical reason to look again, such as monitoring for changes during treatment. If retesting is ever recommended, your trends feature will let you track and compare results over time. Talk with your treatment team about whether your specific situation calls for repeat genetic testing.

What should I do if my results are abnormal?

If your result shows the CRLF2 rearrangement was detected, the most important step is to bring the report to your ongoing leukemia care discussions so it can be considered alongside your other test results. Keep a saved copy of the downloadable lab report for your records. If you're experiencing worsening symptoms like severe fatigue, unexplained bleeding, or fever, seek medical care promptly rather than waiting on routine follow-up.

Getting your blood test with us is easy, private & backed by the power of science.Long story short: In the test options, use the filters or search box to narrow your choices and find the test you want. If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test. Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout. If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want. When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system. Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way. You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy! If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.

How do I know which test to get?

In the test options, find the test you want. If you’re not sure which test to get, we can lend a hand in finding the right option. Just text or call us at 754-799-7833, email us at support@privatemdlabs.com, and we'll gladly help you. We've got your back and reply quickly.

When will my lab results be available?

Most test results will be available within 1–3 business days. Once they're ready, we'll send an email and text message to let you know. After your blood draw, just hang tight and don't worry – we'll keep you updated and in the loop! If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com, and we'll gladly help you.

Is it possible to make changes to my lab order if I made a mistake with the name, date of birth, or any other details?

Absolutely! We totally understand that errors can happen. No worries, we're here to help you. Just reach out to us via text at 754-799-7833 or shoot us an email at support@privatemdlabs.com. Remember to include your order number and let us know the correct information you’d like to update. Our awesome team will jump right in and make sure everything is sorted out and accurate for you. There are no changes necessary if your address is wrong on the requisition though. We don’t mail anything out. Our lab requires an address to be listed to generate an order.

Do you accept health insurance?

Only HSA & FSA is accepted. Our services are strictly self-pay and cannot be submitted to your health insurance provider except for Health Savings Accounts or Flexible Savings Accounts. This policy applies to all insurance companies, including federal health insurance programs like Medicare. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com.

Can I cancel my order?

Yes. We get it – sometimes your needs change. As long as your samples haven’t been collected yet, we’re happy to help you cancel your order. If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com. You can read more about our cancellation policy here.

How can I find a lab location near me?

During the ordering process, you’ll be able to select a specific lab near you, with no strings attached! You can switch it up later easily and visit any of our authorized locations as long as it’s the same lab company you selected your test for (Quest Diagnostics or Labcorp). Before you proceed with your order, feel free to browse through all our lab locations here. This will give you the peace of mind of knowing that there's a lab nearby your home, office or your favorite gym. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.

CRLF2 FISH Test - B-Cell Leukemia Gene Panel

Getting your blood test with us is easy, private & backed by the power of science.

Long story short:

In the test options, use the filters or search box to narrow your choices and find the test you want.
If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test.
Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout.
If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want.
When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system.
Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way.
You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy!

754-799-7833

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