Assessment of a targeted resequencing assay as a support tool in the diagnosis of lysosomal storage disorders

Abstract

BackgroundWith over 50 different disorders and a combined incidence of up to 1/3000 births, lysosomal storage diseases (LSDs) constitute a major public health problem and place an enormous burden on affected individuals and their families. Many factors make LSD diagnosis difficult, including phenotype and penetrance variability, shared signs and symptoms, and problems inherent to biochemical diagnosis. Developing a powerful diagnostic tool could mitigate the protracted diagnostic process for these families, lead to better outcomes for current and proposed therapies, and provide the basis for more appropriate genetic counseling.MethodsWe have designed a targeted resequencing assay for the simultaneous testing of 57 lysosomal genes, using in-solution capture as the enrichment method and two different sequencing platforms. A total of 84 patients with high to moderate-or low suspicion index for LSD were enrolled in different centers in Spain and Portugal, including 18 positive controls.ResultsWe correctly diagnosed 18 positive blinded controls, provided genetic diagnosis to 25 potential LSD patients, and ended with 18 diagnostic odysseys.ConclusionWe report the assessment of a next–generation-sequencing-based approach as an accessory tool in the diagnosis of LSDs, a group of disorders which have overlapping clinical profiles and genetic heterogeneity. We have also identified and quantified the strengths and limitations of next generation sequencing (NGS) technology applied to diagnosis.

Sialidosis type I: ophthalmological findings

“…Although none of these mutations was present in previous cohorts, the observed base change leads to the production of a truncated protein, and so was presumed as causal by the laboratory. The same mutation was later found in other patients with sialidosis type I, as described in more recent papers,2 3 thus reinforcing our previous diagnosis.…”

The neuronal ceroid lipofuscinoses program: A translational research experience in Argentina

“…3 D. Sanger sequencing of CLN8 showed two DNA changes in heterozygous state, exon 2-p.Met1Val (rs143730802) was previously identified in heterozygous state in one patient of African descent, with a general frequency of less than 0.01% [73]. The other DNA variant, exon 3-p.Asn264Lys (rs587779411) was previously identified in homozygous state in an Iberian patient [74]. Both were predicted as deleterious DNA changes by computational approaches (PolyPhen-2 and SIFT softwares predicted them as "probably damaging" and "damaging", respectively).…”

Molecular diagnosis of glycogen storage disease and disorders with overlapping clinical symptoms by massive parallel sequencing

“…4 This very cost-effective technology is particularly appropriate for screening for mutations in disorders with highly heterogeneous genetic backgrounds, such as GSD, congenital disorder of glycosylation, lysosomal disorders, and mitochondrial disorders [5][6][7][8] In addition, its ability to detect mutations in large genes and to identify copy number variations is very advantageous. The implementation of massive parallel sequencing has begun to revolutionize the field of genetic diagnosis.…”