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Private Fragile X Syndrome screen - FMR1 repeat analysis PCR London

Fragile X Syndrome screen - FMR1 repeat analysis PCR is a private test offered at our CQC-registered clinic in Marylebone, London. It should be ordered and interpreted by a registered clinician based on your symptoms and clinical context.

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CQC Registered Clinic
Wimpole Street
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020 7183 0692
Blood Test

Fragile X Syndrome screen - FMR1 repeat analysis PCR

£620

Test fee £620 + £50 phlebotomy fee (per visit)

  • Results in 5 weeks"
  • UKAS accredited laboratory
  • Professional phlebotomy service
  • Confidential results portal
Results in 5 weeks"

Or call 020 7183 0692

Pay at clinic on the day of your appointment

Fragile X Syndrome Screen – FMR1 Repeat Analysis in London

Fragile X Syndrome FMR1 repeat analysis is available at Wimpole Street Medical and Dental, our CQC-registered clinic in Marylebone, London W1G. This test is priced at £620. A £50 phlebotomy fee applies per visit for blood collection. It requires a venous blood sample, and results are typically available within 5 weeks. A referral from a clinical geneticist is required before this test can be ordered.

Fragile X Syndrome is the most common inherited cause of intellectual disability and the most common single-gene cause of autism spectrum disorder. It is caused by an expansion of CGG trinucleotide repeats in the FMR1 gene on the X chromosome. This PCR-based test measures the number of CGG repeats to determine carrier status or affected status.

Who Should Consider Fragile X FMR1 Testing?

Children with developmental delay, intellectual disability, or autism spectrum features, particularly boys. Women with premature ovarian insufficiency (menopause before age 40) or a family history of Fragile X. Men over 50 with progressive tremor and ataxia (Fragile X-associated tremor/ataxia syndrome, FXTAS). Individuals with a family history of intellectual disability or Fragile X.

Normal alleles have 5-44 CGG repeats. Intermediate alleles (45-54 repeats) may be unstable but do not cause Fragile X. Premutation alleles (55-200 repeats) can cause FXTAS in older men and premature ovarian insufficiency in women. Full mutations (over 200 repeats) cause Fragile X Syndrome. Female carriers have a 50% chance of passing the expansion to each child.

A trained nurse collects the blood sample by standard venepuncture at our clinic on Wimpole Street, directly opposite Wimpole Street tube station (Piccadilly, Circle, and District lines). A referral from a clinical geneticist is required — please call 020 7183 0692 to arrange.

Genetic Investigation

Fragile X Syndrome screen - FMR1 repeat analysis PCR provides genetic information that should be ordered alongside appropriate genetic counselling and clinical assessment.

  • Family history of the condition
  • Personal symptoms suggestive of the condition
  • Confirmation of a clinical diagnosis
  • Carrier or reproductive risk assessment
  • Specialist clinical genetics workup
  • Clinician-directed testing

How It Works

1

Book Online

Choose a convenient date and time

2

Visit Our Clinic

22 Wimpole Street, Wimpole Street

3

Quick Blood Draw

Professional phlebotomy, 5 minutes

4

Get Results

Results in 5 weeks"

Frequently Asked Questions

Common questions about this blood test

No fasting is required for this test. You can eat and drink normally before your appointment.

Visit Our London Clinic

Central London location with excellent transport links

Address

Wimpole Street Medical & Dental

22 Wimpole Street

Wimpole Street

London W1G 8GQ

Getting Here

  • 2-minute walk from Wimpole Street tube
  • Circle, District & Piccadilly lines

Opening Hours

  • Monday, Wednesday9am - 6pm
  • Tuesday, Thursday9am - 8pm
  • Friday8am - 5pm
  • Saturday10am - 4pm
  • Sunday10am - 4pm

Contact

020 7183 0692

wimpolestreet@md.co.uk

Ready to Book Your Test?

No GP referral needed. Book online and get tested at our Wimpole Street clinic. Results within 5 weeks".

020 7183 0692

Meet Our Medical Team

Our experienced medical team is fully qualified and registered with the GMC and NMC, delivering safe, high-quality care in line with the highest professional standards.
Because our patients deserve nothing less.

Registered. Regulated. Trusted.

At Wimpole Street Medical & Dental, we are in the process of registering with the Care Quality Commission (CQC) and our clinicians are registered with the relevant UK regulatory bodies, including the GDC and GMC. Our dentists, dental nurses and medical professionals deliver care that meets the highest clinical, safety and ethical standards, because our patients deserve nothing less.

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