Related Experiment Video
Updated: Jun 15, 2026
09:41
Comprehensive Autopsy Program for Individuals with Multiple Sclerosis
Published on: July 19, 2019
Asymmetric phenotype associated with rare myelin protein zero mutation
Nizar Souayah1, Peter Siao Tick Chong
1Department of Neurology and Neurosciences, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA. souayani@umdnj.edu
Journal of Clinical Neuromuscular Disease
|March 11, 2010
Summary
Myelin protein zero (MPZ) gene mutations can cause demyelinating neuropathies. A novel ARG98HIS MPZ mutation identified in a family suggests a cause for hereditary, mild, and asymmetric sensorimotor polyneuropathy.
Area of Science:
- Neurology
- Genetics
- Molecular Biology
Background:
- Myelin protein zero (MPZ) mutations are linked to demyelinating neuropathies with variable severity.
- Hereditary neuropathies present a significant diagnostic challenge, often requiring genetic analysis.
Purpose of the Study:
- To report a novel MPZ mutation (ARG98HIS) identified in a multi-generational family.
- To characterize the clinical phenotype associated with this specific MPZ mutation.
Main Methods:
- Clinical examination of affected individuals across three generations.
- Electrophysiological studies including motor nerve conduction velocities and conduction block assessment.
- Genetic testing to identify the causative MPZ mutation.
Main Results:
- A 36-year-old male presented with progressive asymmetric weakness and electrophysiologically confirmed demyelinating sensorimotor polyneuropathy.
- Genetic analysis revealed a novel ARG98HIS MPZ mutation.
- Affected father and son exhibited overlapping but distinct clinical features, including high-arched feet and asymmetric muscle weakness.
Conclusions:
- The ARG98HIS MPZ mutation is associated with hereditary, relatively mild, and asymmetric demyelinating sensorimotor polyneuropathy.
- This finding expands the genotypic and phenotypic spectrum of MPZ-related neuropathies.
Related Concept Videos
01:33Pleiotropy
Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...
01:25Nervous Tissue: Myelin
The myelin sheath is a multilayered lipid and protein covering that insulates the axon of a neuron, enhancing the speed of nerve impulse conduction. Axons without this sheath are referred to as unmyelinated. Two types of neuroglia, Schwann cells in the peripheral nervous system (PNS) and oligodendrocytes in the central nervous system (CNS) are responsible for producing myelin sheaths.
Schwann cells begin to form myelin sheaths around axons during fetal development. They wrap around a small...
Schwann cells begin to form myelin sheaths around axons during fetal development. They wrap around a small...
02:41Lethal Alleles
Agouti: A Lethal Allele
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...
01:43Incomplete Dominance
Gregor Mendel's work (1822 - 1884) was primarily focused on pea plants. Through his initial experiments, he determined that every gene in a diploid cell has two variants called alleles inherited from each parent. He suggested that amongst these two alleles, one allele is dominant in character and the other recessive. The combination of alleles determines the phenotype of a gene in an organism.
01:19Multiple Sclerosis l: Introduction
Multiple sclerosis is a chronic autoimmune disease of the central nervous system (CNS) that affects the brain, spinal cord, and optic nerves. It is an inflammatory demyelinating disorder and a leading cause of neurological disability in young adults.EpidemiologyMS commonly begins between 20 and 40 years of age and is twice as common in women. Its exact cause remains unclear, but genetic susceptibility contributes, with higher risk in first-degree relatives and identical twins. A greater...