A Comparative Phenotypic Analysis of a PMP22 Heterozygotes Cohort Presenting with Persistent Toe-Walking Versus Classic PMP22-Related Neuropathies

Status

Recruiting

Phases

Unknown

Study type

Observational

Source

DRKS

Registry ID

DRKS00038136

Enrollment

Registered

2025-10-15

Start date

2025-06-25

Completion date

Unknown

Last updated

2025-11-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Q66.8

Interventions

Group 1: This retrospective observational study investigates the phenotypic overlap between a cohort of PMP22 heterozygotes presenting with persistent toe-walking and the classic spectrum of PMP22-rel

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Zehenspitzengang mehr als die Hälfte des Tages Absolvieren eines spezifischen Gentests mit einem Panel von 49 Genen

Exclusion criteria

Exclusion criteria: Abwesenheit von neurologischen/orthopädischen Erkrankungen, wie Zerebralparese, Autismus-Spektrum-Störung, Tethered Cord-Syndrom, Kinder mit Geburtskomplikationen, schwere orthopädische Deformitäten einschließlich Beinlängendifferenzen, Skoliose oder schwere Fußdeformitäten.

Design outcomes

Primary

Measure	Time frame
Comparison of the frequency and severity of clinical features (e.g., toe walking, pes cavus, tremor, muscle weakness, hyporeflexia) between patients with PMP22 heterozygosity and PMP22 HPO heterozygosity.	—

Secondary

Measure	Time frame
Analysis: To contrast the persistent, isolated toe-walking gait in our cohort against the progressive, weakness- and sensory-deficit-driven gait disturbances (e.g., steppage gait, ataxia) characteristic of CMT1A, CMT1E, and HNPP. Musculoskeletal Manifestations: Analysis: To compare the prevalence and nature of structural features (e.g., pes cavus, lumbar hyperlordosis, clinodactyly) in our cohort, hypothesizing a potential developmental origin, against their well-established role as secondary, acquired complications in classic PMP22 neuropathies. Neurological and Motor Profile: Analysis: To systematically compare the neurological signature of our cohort (notably high tremor prevalence, balance disorders, and hyporeflexia) with the classic neurological hallmarks of PMP22-related disorders (areflexia, progressive muscle weakness, sensory loss, and in some cases, hyperreflexia). Notes: The analysis is based on retrospective data from a defined cohort (n=23) compared against established phenotypic frequencies for CMT1A, HNPP, and CMT1E from curated databases (Orphanet, HPO). The study design is observational and comparative, without a prospective control group. The outcomes aim to establish a phenotypic association and delineate a potential novel clinical presentation, not to prove causation.	—

Measure

Time frame

Analysis: To contrast the persistent, isolated toe-walking gait in our cohort against the progressive, weakness- and sensory-deficit-driven gait disturbances (e.g., steppage gait, ataxia) characteristic of CMT1A, CMT1E, and HNPP. Musculoskeletal Manifestations: Analysis: To compare the prevalence and nature of structural features (e.g., pes cavus, lumbar hyperlordosis, clinodactyly) in our cohort, hypothesizing a potential developmental origin, against their well-established role as secondary, acquired complications in classic PMP22 neuropathies. Neurological and Motor Profile: Analysis: To systematically compare the neurological signature of our cohort (notably high tremor prevalence, balance disorders, and hyporeflexia) with the classic neurological hallmarks of PMP22-related disorders (areflexia, progressive muscle weakness, sensory loss, and in some cases, hyperreflexia). Notes: The analysis is based on retrospective data from a defined cohort (n=23) compared against established phenotypic frequencies for CMT1A, HNPP, and CMT1E from curated databases (Orphanet, HPO). The study design is observational and comparative, without a prospective control group. The outcomes aim to establish a phenotypic association and delineate a potential novel clinical presentation, not to prove causation.

—

Countries

Germany

Contacts

Public ContactDavid Pomarino

Pomarino. Praxis für Ganganomalien

forschung@ptz-pomarino.de+49 40 51 32 08 81

Outcome results

None listed

Source: DRKS (via WHO ICTRP) · Data processed: Feb 4, 2026