MYOD1 p.L122R mutational analysis for spindle cell/sclerosing rhabdomyosarcomas

Specimen Requirement	10 unstained sections of tumour and a corresponding H&E-stained histological section, OR 1 paraffin block of tumour
Orderable as Urgent?	No
Turn Around Time	5 Working days
Testing Laboratory Location	KKH
Laboratory	Molecular Pathology
Contact Number	6394 1402
Day and Time Performed	Mon – Fri: 0800 hrs– 1700 hrs
Orderable on CPOE?	No
Downtime Form	Molecular Pathology
Additional Information	Background A proportion of spindle cell/sclerosing rhabdomyosarcomas harbour a recurrent somatic point mutation of the MYOD1 gene c.365T>G p.Leu122Arg resulting in the mutated MyoD1 protein having MYC-like properties. MYOD1-mutated spindle cell/sclerosing RMS have an aggressive clinical course. Purpose of test The test identifies the specific MYOD1 point mutation c.365T>G p.Leu122Arg (p.L122R) by Sanger sequencing. Expected test result MYOD1 p.L122R mutation detected/not detected. Caveats DNA integrity and concentration must meet assay requirements. Low tumour content (<50%) may result in a false negative result. Proficiency testing Alternative performance assessment programme. Reference Kohsaka S et al. A recurrent neomorphic mutation in MYOD1 defines a clinically aggressive subset of embryonal rhabdomyosarcoma associated with PI3K-AKT pathway mutations

Change History Notes

18 Jun 2025 03:59 PM

Update downtime form
12 Apr 2024 04:00 PM

Update of specimen requirement, test name, additional information and editorial edit

Last Updated - 27 Jun 2025