Molecular Genetic Fragile X Syndrome ( FMR1 ) Gene Analysis - NGS
Test Code
MOG22
Also Known As
No data available
Test Parameters Included
No data available
Department
MOLECULAR GENETICS
Methodology
NGS (Next-Generation Sequencing) / PCR / Southern Blot (as confirmatory/supplementary)
The Molecular Genetic Fragile X Syndrome (FMR1) Gene Analysis is a specialized test that, while often utilizing NGS (Next-Generation Sequencing) for broader analysis in some labs, traditionally and crucially relies on PCR (Polymerase Chain Reaction)-based methods and Southern Blot for definitive sizing of the CGG repeat expansion in the FMR1 gene. NGS can be used for initial screening or to detect point mutations/deletions within the FMR1 gene. However, accurately sizing large CGG trinucleotide repeat expansions (full mutations) that characterize Fragile X Syndrome can be challenging for standard short-read NGS. Therefore, a combination of techniques is often employed:
* PCR (particularly Fragile X specific PCR or triplet repeat-primed PCR [TP-PCR]): Used to amplify and size the CGG repeats, especially for normal, intermediate, and premutation ranges.
* Southern Blot: Historically the gold standard and still crucial for definitively sizing the full mutation repeats (typically >200 CGG repeats) and detecting methylation status, which is key for diagnosis in males and affected females. It can resolve larger fragments that NGS or standard PCR may miss or misinterpret.
* NGS (as supplementary): Can be used to detect smaller, less common point mutations or deletions in the FMR1 gene that might also cause Fragile X syndrome, or to provide sequence context if specific CGG repeat sizing isn't the primary goal. However, for direct repeat sizing, it's often complemented by PCR/Southern Blot.
This multi-faceted molecular approach is essential for accurately identifying the number of CGG repeats, which directly correlates with the clinical spectrum of Fragile X Syndrome and related disorders (Fragile X-associated Tremor/Ataxia Syndrome [FXTAS], Fragile X-associated Primary Ovarian Insufficiency [FXPOI]).
Sample Required
Whole Blood (WB) in EDTA Vacutainer
(A sample of whole blood collected in an EDTA vacutainer is required for this test. EDTA acts as an anticoagulant to preserve the blood sample for high-quality DNA extraction.)
Preparation
No specific preparation is typically required for this genetic test. * No Fasting Required: Fasting is not necessary for this blood sample collection. * No Special Timing: Blood can be drawn at any ti... Read more
Schedule Report
30 Days
Emergency Report
Yes
Frequently Asked Questions
No data available
Test Description
- High-end laboratory & medical equipment.
- Outstanding doctor team.
- Personalized care & high-quality service.
- Tailormade health screening packages.