ATN1 Repeat Expansion Testing
Description
Pathogenic CAG repeat expansions in the ATN1 gene have been associated with autosomal dominant dentatorubral-pallidoluysian atrophy (DRPLA). The pathogenic repeat expansions lead to expanded polyglutamine tracts that appear to form toxic neuronal intranuclear aggregates.
Pathogenicity is dependent upon CAG repeat length according to the following ranges 1-2:
Normal Alleles | Mutable Normal Alleles | Intermediate/Uncertain Alleles | Reduced Penetrance Alleles | Full Penetrance Alleles |
6-35 | - | - | 36-47* | 48 or more** |
*Individuals with incompletely penetrant alleles may develop a mild form of DRPLA.
**Full penetrance alleles: Expansions of 48 repeats or more are associated with adult onset. 63 repeats or more are associated with childhood onset.
Tests That Analyze ATN1 Repeats
- Genomic Unity® 2.0
- Genomic Unity® Whole Genome Analysis
- Genomic Unity® Lightning Genome Analysis – Pediatric
- Genomic Unity® Lightning Genome Analysis – Standard
- Genomic Unity® Exome Plus Analysis
- Genomic Unity® Exome Analysis
- Genomic Unity® Movement Disorders Analysis
- Genomic Unity® Comprehensive Ataxia Analysis
- Genomic Unity® Ataxia Repeat Expansion Analysis
- Genomic Inform®