Use long-range PCR and NGS method to detect GLA variations. This test analyzes the GLA gene that has been associated with Fabry disease. Sequencing analysis will be performed on the coding regions of the gene (unless otherwise marked). All analysis is performed utilizing Next Generation Sequencing (NGS) technology. All variants are classified according to ACMG guidelines.

• People with definite symptoms of related genetic diseases.
• People with a family history of related genetic disorders.

Fabry disease is a lysosomal storage disorder with a wide spectrum of symptoms ranging from mild cases in females, to severe cases in classically affected hemizygous males. Symptoms may include abdominal and joint pain, vascular lesions and corneal abnormalities. Neurological symptoms include autonomic dysfunction and burning sensation or numbness in the extremities. Fabry disease affects an estimated 1 in 40,000 to 1 in 60,000 males. The prevalence is unknown in females.

This test uses Long-range PCR and next-generation sequencing technology. Sequencing is performed on genomic DNA. Direct sequencing of the amplified captured regions was performed on Illumina next generation sequencing (NGS) systems. A base is considered to have sufficient coverage at 20X and an exon is considered fully covered if all coding bases plus three nucleotides of flanking sequence on either side are covered at 20X or more. Low coverage regions, if any, are limited to ~1% or less of the nucleotides in the test unless a pathogenic variant explaining the phenotype is discovered. A list of these regions is available upon request. Alignment to the human reference genome (hg19) is performed and annotated variants are identified in the targeted region. Variants are called at a minimum coverage of 8X and an alternate allele frequency of 20% or higher. Single nucleotide variants (SNVs) meeting internal quality assessment guidelines are confirmed by Sanger sequence analysis for records after results are reported. Indels and SNVs are confirmed by Sanger sequence analysis before reporting at director discretion. This assay cannot detect variants in regions of the exome that are not covered, such as deep intronic, promoter and enhancer regions, areas containing large numbers of tandem repeats, and variants in mitochondrial DNA. Copy number variation (CNV) analysis detects deletions and duplications; in some instances, due to the size of the exons, sequence complexity, or other factors, not all CNVs may be analyzed or may be difficult to detect.