Optical brain imaging for X-linked intellectual disabilities

Optical Imaging as a Diagnostic Tool for Monitoring Brain Function in X-linked Rare Disorders

Not applicable Interventional Hospices Civils de Lyon · NCT06868979

This project will try using noninvasive optical brain imaging (fNIRS) together with cognitive tests in males aged 5–35 who have Fragile X syndrome or creatine transporter deficiency to look for patterns of brain function.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment88 (estimated)
Ages5 Years to 35 Years
SexMale
SponsorHospices Civils de Lyon Academic / other
Locations1 site (Bron)
Trial IDNCT06868979 on ClinicalTrials.gov

What this trial studies

This interventional protocol combines functional near-infrared spectroscopy (fNIRS) with clinical, cognitive and reasoning assessments and parental questionnaires to characterize brain activity in affected males and age-matched male controls. Participants undergo standardized cognitive tests and fNIRS recordings during tasks to capture functional brain signatures linked to synaptic connectivity and brain energetics. The study targets males aged 5–35 with genetically confirmed Fragile X full mutation or SLC6A8 mutations and compares them to chronological controls. All visits take place at the Hospices Civils de Lyon site and require French as the maternal language.

Who should consider this trial

Good fit: Ideal candidates are French-speaking males aged 5–35 with a confirmed full mutation in FMR1 (>200 CGG repeats) or a confirmed SLC6A8 mutation, who can give consent or have a parent/guardian provide consent and are affiliated with the French national health insurance.

Not a fit: Females, individuals outside the 5–35 age range, non–French speakers, those without genetic confirmation, or people unable to complete fNIRS or cognitive testing are unlikely to receive direct benefit from participation.

Why it matters

Potential benefit: If successful, the work could provide an objective, noninvasive biomarker of brain function that helps track disease features and guide future treatments for these X-linked conditions.

How similar studies have performed: Previous small studies have applied fNIRS and other functional imaging to neurodevelopmental disorders with promising preliminary findings, but this approach remains exploratory for Fragile X and creatine transporter deficiency.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria :

CTD patients :

* male
* having a confirmed mutation in the SLC6A8 gene
* ≥ 5 to ≤ 35 years old
* whose maternal language is French,
* having signed the informed consent and/or for whom parents (for children)/legal guardian (for protected adults) have signed the informed consent.
* affiliated to national Health Insurance system (sécurité sociale) or parents/legal guardian affiliated to national health insurance system

FXS patients :

* male
* having a confirmed full mutation in the FMR1 gene (\>200 GCC repeats)
* ≥ 5 to ≤ 35 years old
* whose maternal language is French,
* having signed the informed consent and/or for whom parents (for children)/legal guardian (for protected adults) have signed the informed consent.
* affiliated to national Health Insurance system (sécurité sociale) or parents/legal guardian affiliated to national health insurance system

Chronological age-matched controls :

* male
* ≥ 5 to ≤ 35 years old
* whose maternal language is French,
* having signed the informed consent and/or for whom parents have signed the informed consent.
* affiliated to national Health Insurance system (sécurité sociale) or parents/legal guardian affiliated to national health insurance system

Exclusion Criteria:

CTD patients :

* Refusal of the subject and/or the subject's parents/legal guardian to sign the informed consent
* Refusal of the subject and/or the subject's parents/legal guardian to be informed of possible abnormalities detected during the neuropsychological assessment.

FXS patients :

* Refusal of the subject and/or the subject's parents/legal guardian to sign the informed consent
* Refusal of the subject and/or the subject's parents/legal guardian to be informed of possible abnormalities detected during the neuropsychological assessment.

Chronological age-matched controls :

* Refusal of the subject and/or the subject's parents/legal guardian to sign the informed consent
* Refusal of the subject and/or the subject's parents/legal guardian to be informed of possible abnormalities detected during the neuropsychological assessment.
* History of neurological or psychiatric disorder,
* Repetition of a grade,
* Learning disability requiring rehabilitation (speech therapy, psychomotor or oculomotor therapy).

Where this trial is running

Bron

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Fragile X SyndromeCreatine Transporter DeficiencyFragile X syndromeOptical imagingbrain functionCreatine transportercognitive functionreasoning tasks
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.