FB2026_01 , released March 12, 2026
FB2026_01 , released March 12, 2026
Human Disease Model Report: Charcot-Marie-Tooth disease, axonal, type 2DD
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General Information
Name
Charcot-Marie-Tooth disease, axonal, type 2DD
FlyBase ID
FBhh0001579
Overview

This report describes Charcot-Marie-Tooth disease, axonal, type 2DD, a subtype of Charcot-Marie-Tooth disease type 2; CMT2 is characterized by abnormalities in the axons of peripheral nerve cells. The human gene implicated is ATP1A1, which encodes the alpha-1 isoform of the Na(+),K(+)-ATPase. There is one high-scoring fly ortholog, Dmel\Atpα, for which multiple genetic reagents, including classical alleles, RNAi-targeting constructs, and alleles caused by insertional mutagenesis have been generated.

Human ATP1A1 has not been introduced into flies.

A number missense mutations analogous to those implicated in this disease have been introduced into the Dmel\Atpα gene by homologous recombination; see the 'Disease-Implicated Variants' table below. In addition, a single gene carrying four such disease-implicated missense variants has been generated. Flies bearing disease-implicated variant-analogous alleles of Atpα display motor and sensory defects, and have an abnormal circadian neuron dendritic morphology. Mutant flies have significantly decreased Na+/K+-ATPase activity, and a decreased lifespan when fed a high Na+ diet.

Several other human diseases associated with the related human genes ATP1A2 and ATP1A3 have been studied in flies using the Dmel\Atpα gene; see the Human Disease Model report 'neurological disorders, ATPα-related' (FBhh0000547).

[updated Oct. 2024 by FlyBase; FBrf0222196]

Disease Summary Information
Parent Disease Summary: Charcot-Marie-Tooth disease
Symptoms and phenotype

Charcot-Marie-Tooth disease (CMT) constitutes a clinically and genetically heterogeneous group of hereditary motor and sensory peripheral neuropathies. CMT is divided into several major types: Type 1 is characterized by demyelination and by a significantly slowed motor median nerve conduction velocity (NCV). Type 2 is characterized by axonal abnormalities and a normal or slightly reduced NCV. "Intermediate" types describe CMT families with nerve conduction velocities, in different affected individuals, that overlap the division between Type 1 and Type 2. Additional types are defined on the basis inheritance patterns. [from MIM:609260 and MIM:606482; 2015.12.15]

Symptoms typically include progressive distal muscle weakness and atrophy, often associated with mild to moderate sensory loss, depressed tendon reflexes, and high-arched feet. [from Gene Reviews, http://www.ncbi.nlm.nih.gov/books/NBK1358 2015.12.15]

Specific Disease Summary: Charcot-Marie-Tooth disease, axonal, type 2DD
OMIM report

[CHARCOT-MARIE-TOOTH DISEASE, AXONAL, TYPE 2DD; CMT2DD](https://omim.org/entry/618036)

Human gene(s) implicated

[ATPase, Na+/K+ TRANSPORTING, ALPHA-1 POLYPEPTIDE; ATP1A1](https://omim.org/entry/182310)

Symptoms and phenotype

Charcot-Marie-Tooth disease type 2DD is an autosomal dominant peripheral sensorimotor neuropathy mainly affecting the lower limbs. Affected individuals have gait impairment due to distal muscle weakness and atrophy. Some patients may also have involvement of the distal upper limbs, resulting in atrophy of the intrinsic hand muscles. The age at onset and severity of the disorder is highly variable, even within families, and those with earlier onset in late childhood or the teenage years tend to have a more severe disease course. Patients remain ambulatory even late in the disease, although some may require orthotic devices (summary by Lassuthova et al., 2018, pubmed:29499166) [from MIM:618036; 2024.05.31]

Genetics

Autosomal dominant axonal Charcot-Marie-Tooth disease type 2DD (CMT2DD) is caused by heterozygous mutation in the ATP1A1 gene on chromosome 1p13. [from MIM:618036; 2024.05.31]

Cellular phenotype and pathology
Molecular information

The ATP1A1 gene encodes the alpha-1 isoform of the Na(+),K(+)-ATPase, an integral membrane protein responsible for establishing and maintaining the electrochemical gradients of Na and K ions across the plasma membrane. As these gradients are essential for osmoregulation, for sodium-coupled transport of a variety of organic and inorganic molecules, and for electrical excitability of nerve and muscle, the enzyme plays an essential role in cellular physiology. It is composed of at least 2 subunits, a large catalytic subunit (alpha) and a smaller glycoprotein subunit (beta) (ATP1B1. ATP1A1 and ATP1A2 are isoforms of the catalytic subunit. Kidney contains predominantly ATP1A1, whereas both subunits are found in brain, adipose tissue, and skeletal muscle (summary by Shull and Lingrel, 1987, pubmed:3035563). [from MIM:182310; 2024.05.31]

External links
Disease synonyms
Charcot-Marie-Tooth neuropathy, type 2DD
CMT2DD
Ortholog Information
Human gene(s) in FlyBase
    Human gene (HGNC)
    D. melanogaster ortholog (based on DIOPT)
    Comments on ortholog(s)

    Many to many (many human to many Drosophila); ATP1A1 has one high-scoring Drosophila ortholog, Atpα, and one moderate scoring ortholog, JYalpha

    Other mammalian ortholog(s) used
      D. melanogaster Gene Information (2)
      Gene Snapshot
      JYalpha (JYalpha) is a gene essential for male fertility as mutants produce immotile sperm. [Date last reviewed: 2019-03-14]
      Cellular component (GO)
      Gene Groups / Pathways
      Comments on ortholog(s)

      Moderate-scoring ortholog of human ATP1A1, ATP12A, ATP1A2, ATP1A3, ATP1A4, and ATP4A (many Drosophila to many human).

      Orthologs and Alignments from DRSC
      DIOPT - DRSC Integrative Ortholog Prediction Tool - Click the link below to search for orthologs in Humans
      Gene Snapshot
      Na pump α subunit (Atpα) encodes an integral membrane cation antiporter protein that utilizes ATP to shuttle Na[+] and K[+] across the plasma membrane to maintain ion homeostasis. [Date last reviewed: 2019-03-07]
      Gene Groups / Pathways
      Comments on ortholog(s)

      High-scoring ortholog of human ATP1A3, ATP1A1, ATP1A2, ATP1A4; moderate scoring ortholog of human ATP12A and ATP4A (many Drosophila to many human).

      Orthologs and Alignments from DRSC
      DIOPT - DRSC Integrative Ortholog Prediction Tool - Click the link below to search for orthologs in Humans
      Other Genes Used: Viral, Bacterial, Synthetic (0)
        Summary of Physical Interactions (29 groups)
        protein-protein
        Interacting group
        Assay
        References
        anti tag coimmunoprecipitation, Identification by mass spectrometry
        experimental knowledge based
        anti tag coimmunoprecipitation, Identification by mass spectrometry
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        anti tag coimmunoprecipitation, peptide massfingerprinting
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        pull down, molecular weight estimation by staining, anti tag coimmunoprecipitation, anti tag western blot
        experimental knowledge based
        enzymatic study, western blot
        experimental knowledge based
        experimental knowledge based
        experimental knowledge based
        anti tag coimmunoprecipitation, peptide massfingerprinting
        experimental knowledge based
        Alleles Reported to Model Human Disease (Disease Ontology) (16 alleles)
        Models Based on Experimental Evidence ( 16 )
        Modifiers Based on Experimental Evidence ( 3 )
        Allele
        Disease
        Interaction
        References
        is ameliorated by Pur1
        is ameliorated by Dyrk21
        is ameliorated by GαoMI00833
        is ameliorated by Sec152
        is ameliorated by cact7
        is ameliorated by painEP2451
        is ameliorated by slmb00295
        is ameliorated by spz5e03444
        Alleles Representing Disease-Implicated Variants
        Genetic Tools, Stocks and Reagents
        Sources of Stocks
        Contact lab of origin for a reagent not available from a public stock center.
        Bloomington Stock Center Disease Page
        Related mammalian, viral, bacterial, or synthetic transgenes
        Allele
        Transgene
        Publicly Available Stocks
        Selected Drosophila transgenes
        Allele
        Transgene
        Publicly Available Stocks
        RNAi constructs available
        Allele
        Transgene
        Publicly Available Stocks
        Selected Drosophila classical alleles
        Allele
        Allele class
        Mutagen
        Publicly Available Stocks
        P-element activity
        CRISPR/Cas9
        CRISPR/Cas9
        CRISPR/Cas9
        CRISPR/Cas9
        CRISPR/Cas9
        CRISPR/Cas9
        loss of function allele
        gamma ray
        loss of function allele
        gamma ray
        loss of function allele
        gamma ray
        ethyl methanesulfonate
        loss of function allele
        gamma ray
        ethyl methanesulfonate
        ethyl methanesulfonate
        ethyl methanesulfonate
        ethyl methanesulfonate
        ethyl methanesulfonate
        ethyl methanesulfonate
        References (6)