Design of a multiplex ligation-dependent probe amplification assay for SLC20A2: identification of two novel deletions in primary familial brain calcification.

Primary familial brain calcification (PFBC) is a rare disease characterized by brain calcifications that mainly affect the basal ganglia, thalamus, and cerebellum. Among the four autosomal-dominant genes known to be associated with the disease, SLC20A2 pathogenic variants are the most common, accounting for up to 40% of PFBC dominant cases; variants include both point mutations, small insertions/deletions and intragenic deletions. Over the last 7 years, we have collected a group of 50 clinically diagnosed PFBC patients, who were screened for single nucleotide changes and small insertions/deletions in SLC20A2 by Sanger sequencing.