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Acatalasemia Test

Genes:
CAT

Syndrome Information

Clinical Description

Patients with acatalasemia have a defect in the enzyme catalase encoded by the gene CAT.  The defect is most profound in erythrocytes.  This is a rare disorder that may also be referred to as Takahara disease or acatalasia.  Patients may develop oral lesions that become gangrenous, but about half of individuals may not experience any known adverse effects of the deficiency.

Inheritance Pattern

Autosomal Recessive

Genotype-Phenotype Correlation

Missense mutations may be associated with milder clinical and biochemical phenotypes

Test Information

Test Method

Next Generation Sequencing (NGS) of the coding regions and intron-exon boundaries of CAT; Deletion/Duplication:  Dosage analysis by normalization of NGS read depth for CAT; Sanger sequencing for potential fill in / confirmation 

This test is also available as part of one or more NGS panels for peroxisomal disorders.

Clinical Utility

Identification of causative mutations in known or suspicious cases of acatalasemia; rule-out in the presence of equivocal clinical presentation and/or biomarker profile; targeted carrier testing of relatives of proband; predictive prenatal testing when familial mutations are known

Clinical Sensitivity

CAT is the only gene reported to be associated with acatalasemia.  This analysis will identify two mutations in >98% of patients with deficient erythrocyte catalase activity.  There have been no reports of CAT deletions or duplications.

Analytic Sensitivity

> 99% for inherited single nucleotide and small insertion/deletion variants for the nucleotides evaluated; >99% for multi-exon deletions and >98% for single exon deletions; >90% for multi-exon duplications and >75% for single exon duplications. Lower limit of detection for single nucleotide variants: 25% allele frequency (>99% sensitivity).

Sample Requirements

3-6ml whole blood in EDTA (purple topped) tubes. (see Pediatric or Adult blood sample algorithms for additional information)

We prefer whole blood for all tests.

Turn Around Time

 Approximately 4 weeks

Fee and CPT Codes

$2450 for routine testing
CPT Code:  81479

Special Considerations

We request that copies of the patient's biochemical analysis be submitted with the sample.

NGS panels for peroxisomal disorders

INFORMED CONSENT from the patient is required prior to ordering a genetic test. The DNA Diagnostic Lab's consent is located on the second page of the requisition form. There is also a patient brochure, "Things Every Patient Should Know Before Consenting to a Genetic Test", available for download.