Long-read genetic analysis for Spinal Muscular Atrophy (LOREASI)
Detection of Cis Duplications of the SMN1 Gene Using Long-read Analysis to Address a Major Issue in Genetic Counseling for Spinal Muscular Atrophy
This project tries a long-read DNA technique on adults with known SMN1 copy-number patterns to find hidden '2+0' carrier genotypes that standard tests miss.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 27 (estimated) |
| Ages | 18 Years and up |
| Sex | All |
| Sponsor | University Hospital, Rouen Academic / other |
| Locations | 1 site (Rouen) |
| Trial ID | NCT07332702 on ClinicalTrials.gov |
What this trial studies
Spinal Muscular Atrophy (SMA) is caused by loss of the SMN1 gene, and some carriers are not detected because two SMN1 copies can sit side-by-side on one chromosome (a 2+0 genotype). This study uses ultra-long molecule analysis and optical mapping (Bionano) on blood samples to detect cis duplications of SMN1 in the complex 5q11-q13 region. Participants with 1 or 3 SMN1 copies serve as controls while those with 2 copies in cis (2+0) form the test group, allowing comparison of detection performance against current diagnostic approaches. The goal is to determine whether these technologies can reliably reveal 2+0 genotypes to improve genetic counseling and carrier screening.
Who should consider this trial
Good fit: Adults affiliated with French health insurance who have prior SMN1 copy-number results showing 1 or 3 copies (controls) or 2 copies in cis (2+0, test group) and who can give informed consent are ideal candidates.
Not a fit: Pregnant or breastfeeding women, individuals under legal guardianship or detention, people without relevant SMN1 copy-number data, or those outside the French health system are unlikely to benefit from participation.
Why it matters
Potential benefit: If successful, the technique could reduce missed SMA carriers and improve accuracy of preconception genetic counseling.
How similar studies have performed: Early research using long-read sequencing and optical mapping has shown promise for resolving complex SMN1/SMN2 rearrangements, but routine clinical detection of 2+0 genotypes remains largely novel.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria • Adult Subject: * Subject with either: * 1 or 3 copies of the SMN1 gene (control group) and a variable number of copies of the SMN2 gene * 2 copies of the SMN1 gene in cis (2+0 genotype) (test group) * Affiliation to French health insurance * Signed consent form Exclusion Criteria * Pregnant or breastfeeding women * Individuals deprived of liberty by an administrative or judicial decision, or those under guardianship or curatorship
Where this trial is running
Rouen
- CHU Rouen — Rouen, France (Recruiting)
Study contacts
- Study coordinator: Pascale Saugier-Veber, PharmD PhD
- Email: Pascale.Saugier-Veber@chu-rouen.fr
- Phone: (+33) 2 32 88 64 51
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.