Related Experiment Video
Updated: Jun 14, 2026
09:37
A Phenotyping Regimen for Genetically Modified Mice Used to Study Genes Implicated in Human Diseases of Aging
Published on: July 14, 2016
ABCA4 and ROM1: implications for modification of the PRPH2-associated macular dystrophy phenotype
Charlotte M Poloschek1, Michael Bach, Wolf A Lagrèze
1Department of Ophthalmology, University of Freiburg, Freiburg, Germany. charlotte.poloschek@uniklinik-freiburg.de
Investigative Ophthalmology & Visual Science
|March 26, 2010
Summary
Genetic mutations in PRPH2, ABCA4, and ROM1 genes influence the severity of inherited retinal diseases. Additional mutations worsen the phenotype, impacting visual prognosis and genetic counseling for macular dystrophy.
Area of Science:
- Ophthalmology
- Genetics
- Molecular Biology
Background:
- Autosomal dominant macular dystrophy, cone dystrophy, and cone-rod dystrophy exhibit significant intrafamilial phenotypic variation.
- Identifying causative mutations and modifier genes is crucial for understanding disease progression and providing accurate genetic counseling.
Purpose of the Study:
- To pinpoint the genetic mutation responsible for inherited retinal dystrophies in a multi-generational family.
- To investigate the role of modifier genes in explaining the wide spectrum of clinical presentations observed within the family.
Main Methods:
- Comprehensive ophthalmic and electrophysiologic evaluations were performed on 15 family members.
- Mutation screening involved microarrays for known retinal degeneration genes and targeted sequencing of PRPH2, ABCA4, and ROM1.
Main Results:
- Heterozygous mutations in PRPH2 (p.R172W) were present in all severely affected individuals.
- Additional mutations in ROM1 (p.R229H) or ABCA4 (p.V2050L) modulated the phenotype, with combined mutations leading to the most severe disease.
- Mild phenotypes were observed in individuals with isolated ROM1 or ABCA4 mutations.
Conclusions:
- The PRPH2-associated retinal dystrophy phenotype is influenced by additional genetic mutations in ABCA4 and/or ROM1.
- These modifier genes contribute to intrafamilial variability and a cumulative effect that worsens the disease phenotype.
- Testing for ABCA4 and ROM1 mutations in families with PRPH2-related macular dystrophy is recommended to refine genetic counseling regarding visual loss progression.
