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Updated: May 12, 2026
10:17
An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
Genetic basis of hyperlysinemia.
Sander M Houten1, Heleen Te Brinke, Simone Denis
1Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands. s.m.houten@amc.uva.nl
Orphanet Journal of Rare Diseases
|April 11, 2013
Summary
Genetic mutations in the AASS gene cause hyperlysinemia, a disorder of L-lysine degradation. Novel mutations were identified, including a contiguous gene deletion syndrome impacting neurological disease severity.
Area of Science:
- Biochemistry
- Genetics
- Metabolic Disorders
Background:
- Hyperlysinemia is an inherited metabolic disorder affecting L-lysine breakdown.
- Previously, only one mutation in the AASS gene was linked to this condition.
- The genetic underpinnings of hyperlysinemia require further elucidation.
Purpose of the Study:
- To investigate the genetic basis of hyperlysinemia.
- To identify novel mutations in the AASS gene.
- To correlate genetic findings with clinical and biochemical data.
Main Methods:
- Collected clinical, biochemical, and molecular data from 8 hyperlysinemia patients.
- Performed genetic analysis to identify mutations in the AASS gene.
- Investigated contiguous gene deletions.
Main Results:
- Identified novel causal mutations in the AASS gene in all patients.
- Discovered missense mutations, deletions, and a duplication in AASS.
- Found a contiguous gene deletion syndrome involving AASS and PTPRZ1 in two patients.
Conclusions:
- Mutations in the AASS gene are the cause of hyperlysinemia.
- The contiguous deletion of AASS and PTPRZ1 may explain severe neurological symptoms.
- Emphasizes the need for comprehensive genetic and biochemical evaluation in hyperlysinemia cases.
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