Table 1.

Molecular Genetic Testing Used in Free Sialic Acid Storage Disorders

Gene 1MethodProportion of Pathogenic Variants 2 Detectable by Method
SLC17A5 Sequence analysis 390%-95% 4, 5
Gene-targeted deletion/duplication analysis 65%-10% 4, 7
1.
2.

See Molecular Genetics for information on variants detected in this gene.

3.

Sequence analysis detects variants that are benign, likely benign, of uncertain significance, likely pathogenic, or pathogenic. Variants may include missense, nonsense, and splice site variants and small intragenic deletions/insertions; typically, exon or whole-gene deletions/duplications are not detected. For issues to consider in interpretation of sequence analysis results, click here.

4.

The p.Arg39Cys variant, known as the "FIN" variant, is common in the Finnish and other Nordic populations; therefore, a higher detection rate by sequencing is expected in those populations [Peltonen et al 1999, Aula et al 2000].

5.
6.

Gene-targeted deletion/duplication analysis detects intragenic deletions or duplications. Methods used may include a range of techniques such as quantitative PCR, long-range PCR, multiplex ligation-dependent probe amplification (MLPA), and a gene-targeted microarray designed to detect single-exon deletions or duplications.

7.

From: Free Sialic Acid Storage Disorders

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