Early phenotypical diagnoses in Trembler-J mice model

Area of Science:

• Neuroscience
• Genetics
• Animal Models

Background:

• Charcot-Marie-Tooth type 1A (CMT1A) is a peripheral neuropathy.
• Pmp-22 mutant mice (Trembler-J) serve as a model for CMT1A research.
• Early identification of genotypes is crucial for managing CMT1A mouse colonies.

Purpose of the Study:

• To develop a rapid, simple, and non-invasive diagnostic method for identifying Pmp-22 mutation in Trembler-J mice.
• To enable early detection of the heterozygous genotype at postnatal day 11.
• To correlate behavioral phenotypes with specific genotypes.

Main Methods:

• Modification of the Tail Suspension Test (MTST) to differentiate Trembler-J mice from wild-type littermates.
• Observation of animal behavioral phenotypes during the MTST.
• Utilizing the Fixed Bar Test (FBT) to analyze motor impairment and disease progression over time.

Main Results:

• The MTST successfully distinguished between Trembler-J and wild-type mice based on behavioral phenotypes.
• The MTST allowed for the inference of heterozygous genotype at 11 days postnatal.
• The FBT demonstrated age-dependent motor impairment in Trembler-J mice.

Conclusions:

• The modified Tail Suspension Test (MTST) is an objective, simple, and rapid method for early diagnosis of the Pmp-22 mutation in Trembler-J mice.
• The MTST is a welfare-friendly, non-invasive technique suitable for early-stage application in mouse models.
• This method aids in routine genotype identification and management of CMT1A research colonies.