GENEXPLOR: Search for Structural Variants in Patients With DSD and Inconclusive Molecular Diagnosis

Sponsor
University Hospital, Montpellier (Other)
Overall Status
Not yet recruiting
CT.gov ID
NCT05867979
Collaborator
(none)
20
1
1
24
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Study Details

Study Description

Brief Summary

The goal of this clinical trial is to identify structural variants by Optical Genome Mapping (OGM) in the described participant population.

The main questions it aims to answer are:
  • Identify constitutional structural variants by OGM of DNA extracted from blood leukocytes of patients with DSD for which the molecular diagnosis is inconclusive.

  • Identify mosaic structural variants (present in a subpopulation of somatic cells only) by OGM of DNA extracted from blood leukocytes of patients with DSD for which the molecular diagnosis is inconclusive.

  • Compare the diagnostic yields of OGM and of Comparative Genome Hybridization Array (CGH array) methods.

  • Compare the diagnostic yields of the OGM and of Whole Genome Sequencing (National Sequencing Program), only if performed.

Participants will be required to:
  • a follow-up interview with a physician to review their own and family medical and surgical history, with a focusing on DSD.

  • An interview to assess their exposure to environmental pollutants during fetal life, using a validated questionnaire.

  • a blood test with a 5mL tube to perform optical genome mapping analysis.

Condition or Disease Intervention/Treatment Phase
  • Diagnostic Test: Identify structural variants by Optical Genome Mapping of DNA extracted from blood leukocytes
N/A

Detailed Description

Patients with severe or moderate disorder of sex development (DSD) with a inconclusive molecular diagnosis will benefit from optical genome mapping analysis.

A venous blood sample on ethylenediaminetetraacetic acid (EDTA) tube (5mL) will be taken in order to extract the DNA that will be used for the optical genome mapping analysis.

Study Design

Study Type:
Interventional
Anticipated Enrollment :
20 participants
Allocation:
N/A
Intervention Model:
Single Group Assignment
Intervention Model Description:
This is a single-center molecular biology pilot study on a single group of 20 patients with a disorder of sex development and inconclusive molecular diagnosis. The 20 blood samples from patients with severe or moderate DSD, with an inconclusive diagnosis will benefit from the Optical Genome Mapping.This is a single-center molecular biology pilot study on a single group of 20 patients with a disorder of sex development and inconclusive molecular diagnosis. The 20 blood samples from patients with severe or moderate DSD, with an inconclusive diagnosis will benefit from the Optical Genome Mapping.
Masking:
None (Open Label)
Primary Purpose:
Diagnostic
Official Title:
Search for Structural Variants in Patients With Disorders of Sex Development (DSD) and Inconclusive Molecular Diagnosis GENEXPLOR-DSD
Anticipated Study Start Date :
Jun 15, 2023
Anticipated Primary Completion Date :
Jun 15, 2025
Anticipated Study Completion Date :
Jun 15, 2025

Arms and Interventions

Arm Intervention/Treatment
Experimental: patients with DSD and inconclusive molecular diagnosis

The one arm of the study will have a venous blood draw as part of the research. 1 EDTA tube of 5mL will be collected.

Diagnostic Test: Identify structural variants by Optical Genome Mapping of DNA extracted from blood leukocytes
The one arm of the study will have a venous blood draw as part of the research. 1 EDTA tube of 5mL will be collected.

Outcome Measures

Primary Outcome Measures

  1. Presence of constitutional structural variants detected by OGM [Day of inclusion]

    A structural variant, present at the constitutional state in leukocyte DNA, and considered as likely pathogenic or pathogenic, identified by OGM in at least one of the included patients.

Secondary Outcome Measures

  1. Presence of mosaic structural variants detected by OGM [Day of inclusion]

    A structural variant, present at the mosaic state in leukocyte DNA (i.e. allelic imbalance less than 0.40), and considered as likely pathogenic or pathogenic, identified by OGM in at least one of the included patients.

Eligibility Criteria

Criteria

Ages Eligible for Study:
6 Months and Older
Sexes Eligible for Study:
Male
Accepts Healthy Volunteers:
No
Inclusion Criteria:
  • homogeneous XY male karyotype.

  • patient at least 6 months old

  • severe to moderate DSD (Prader 1 to 5) for which the molecular diagnosis is inconclusive after a gene panel analysis.

Exclusion Criteria:
  • subject with a homogeneous or mosaic XX, or monosomal X karyotype.

  • subject with an aneuploidy.

  • subject with a conclusive molecular diagnosis explaining the observed DSD (i.e. carrier of a causal genotype already well characterized by functional studies)

Contacts and Locations

Locations

Site City State Country Postal Code
1 University Hospital Montpellier Montpellier France 34000

Sponsors and Collaborators

  • University Hospital, Montpellier

Investigators

  • Principal Investigator: Françoise PARIS, MD PhD, University Hospital, Montpellier

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.
Responsible Party:
University Hospital, Montpellier
ClinicalTrials.gov Identifier:
NCT05867979
Other Study ID Numbers:
  • RECHMPL 22_0236
First Posted:
May 22, 2023
Last Update Posted:
May 22, 2023
Last Verified:
May 1, 2023
Individual Participant Data (IPD) Sharing Statement:
No
Plan to Share IPD:
No
Studies a U.S. FDA-regulated Drug Product:
No
Studies a U.S. FDA-regulated Device Product:
No
Additional relevant MeSH terms:

Study Results

No Results Posted as of May 22, 2023