Gene Function

Scaffolding protein that functions as part of a dystroglycan complex in Schwann cells, and as part of EZR and AHNAK-containing complexes in eye lens fiber cells. Required for the maintenance of the peripheral myelin sheath that is essential for normal transmission of nerve impulses and normal perception of sensory stimuli. Required for normal transport of MBP mRNA from the perinuclear to the paranodal regions. Required for normal remyelination after nerve injury. Required for normal elongation of Schwann cells and normal length of the internodes between the nodes of Ranvier. The demyelinated nodes of Ranvier permit saltatory transmission of nerve impulses; shorter internodes cause slower transmission of nerve impulses. Required for the formation of appositions between the abaxonal surface of the myelin sheath and the Schwann cell plasma membrane; the Schwann cell cytoplasm is restricted to regions between these appositions. Required for the formation of Cajal bands and of Schmidt-Lanterman incisures that correspond to short, cytoplasm-filled regions on myelinated nerves. Recruits DRP2 to the Schwann cell plasma membrane. Required for normal protein composition of the eye lens fiber cell plasma membrane and normal eye lens fiber cell morphology Source: UniProt

Relationship to CMT

CMT4 AR
1 subtype
19q13.2

First described 2001

Subtype	Inheritance	Class	OMIM	Sentinel Publication
SubtypeCMT4F	Inheritanceautosomal recessive	ClassCMT4	OMIM614895	Sentinel Publication A Mutation in Periaxin is Responsible for CMT4F, an Autosomal Recessive form of Charcot-Marie-Tooth Disease 2001 · 10.1093/hmg/10.4.415

Stored Identifiers

HGNC Aliases: KIAA1620

hgnc_idHGNC:13797

ensembl_gene_idENSG00000105227

coords_grch38chr19:40393764-40415070

coords_grch37chr19:40899675-40919273

entrez_id57716

omim_gene605725

uniprot_idsQ9BXM0

refseq_accessionNM_020956

mane_refseqNM_181882.3

mane_ensemblENST00000324001.8

External recordsHGNC:13797OMIM 605725gnomADUniProt Q9BXM0ClinGenClinVar P/LPOrphanetMANE NM_181882.3

EvidenceClinGen Definitive Charcot-Marie-Tooth disease type 4PanelApp Green

ClinVar Variants

Pathogenic and likely pathogenic variants in PRX, as classified in ClinVar, are read live from NCBI. Only aggregate germline records are shown. Uncertain and conflicting classifications are not. Experts in CMT makes no claim to the accuracy of ClinVar data. This index is provided for informational purposes only.

Review stars are ClinVar’s measure of how well a classification is supported: four for a practice guideline, three for an expert panel review, two for agreement among multiple submitters, one for a single submitter with criteria provided, and none where no criteria were provided.

Reported in CMT

Reported in Other Diseases

Reported in a disease other than CMT. Listed apart rather than counted as CMT variants.

Variants w/o a Recorded Disease

Pathogenic or likely pathogenic in ClinVar, submitted without a disease recorded.

The Dorsal Root

A Name That Does Too Much Work

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When Medicine Lost Its Compass

Evidence failed not because it was wrong, but because it was weaponized. I lived the downstream effects of that failure for more than a decade. This is what happens when medicine forgets that data always ends in a human being.

Error 404: Gene Not Found

CMT genetic testing often fails to identify the cause of the disease, even when comprehensive panels are used. Here, we discuss why this happens, what genetic tests can and cannot do, and why a negative result still matters.