Test Type |
Genes Available |
Pros |
Cons |
Best Use |
Labs |
---|---|---|---|---|---|
Single Gene Sequencing (Traditional genetic testing) | PMP22, MPZ, GJB1, MFN2, LITAF, EGR2, RAB7, GARS, FEFL, HSPB1, HSPB8, GDAP1, SH3TC2, PRX, FIG4, DNM2, YARS, FGD4, NDRG1, TRPV4, MTMR2, SBF2, etc. | Good historical database to track variants of uncertain significance; Quick turn around time | If testing for more than one gene, can get expensive. | If it is easy to narrow down the most likely type of CMT to one to three genes based on clinical presentation and family history. | GeneDx, Athena, Medical Neurogenetics, Prevention Genetics |
Next Generation Sequencing | AARS , ATL1; DNM2; DNMT1; DYNC1H1; EGR2; FGD4; GARS; GDAP1; GJB1; GLA; HSPB1; HSPB8; KIF1B; LITAF; LMNA; LRSAM1; MED25; MFN2; MPZ; MTMR2; NDRG1; NEFL; PMP22; PRX; RAB7A; SBF2; SCN9A; SH3TC2; SPTLC2; TRPV4; TTR; YARS | Cheap | Many of the genes are only peripherally associated with CMT – just known to cause peripheral neuropathy. Sequencing more genes can lead to more variants and not necessarily a clear result. Deletions and duplications not picked up as well as in traditional testing or CGH. Turn around time can be lengthy. | Unusual presentation of CMT. | GeneDx, Medical Neurogenetics, InVitae, Prevention Genetics |
Microarray Testing (AKA array CGH, aCGH) | PMP22 duplication/deletion | Cheap and quick | Can only be used to determine if someone has CMT1A or HNPP. Can pick up incidental findings if there are duplications or deletions in other parts of the genome. | If someone has classical signs of CMT1A or HNPP, it is the cheapest way to determine if the duplication or deletion is present. | Countless options – many universities will have their own on-site platform. Others: GeneDx, Signature Genomics, Lineagen, Baylor College of Medicine |
Familial Testing | Any gene that has been previously identified in the family. This testing can look for just the one mutation that was previously found in the family. | Cheap, precise | None | Testing after there is a found disease-causing genetic mutation in someone else in the family. | The lab where the original testing was performed. If testing was performed on a research basis, some labs will confirm the single mutation, including University of Chicago and GeneDx. |