We report on two novel variants in the PSAP gene - c.679_681delAAG in the saposin B encoding exon 6 and c.1268delT in the saposin D encoding exon 11 in a patient with MLD.
Metachromatic leukodystrophy (MLD) is a rare lysosomal disorder caused by deficient activity of arylsulfatase A or the lack of saposin B, which results in the accumulation of sulfatide in the oligodendrocytes and in the Schwann cells.
Prosaposin deficiency and saposin B deficiency (activator-deficient metachromatic leukodystrophy): report on two patients detected by analysis of urinary sphingolipids and carrying novel PSAP gene mutations.
Molecular analysis of ARSA and PSAP genes in twenty-one Italian patients with metachromatic leukodystrophy: identification and functional characterization of 11 novel ARSA alleles.
We identified a previously undescribed mutation (N215K) in the prosaposin gene of a patient with metachromatic leukodystrophy but with normal arylsulphatase A activity and elevated sulphatide in urine.
Recently, patients have been identified who have a variant form of metachromatic leukodystrophy which is characterized by mutations in the gene coding for SAP-1, which is also called "prosaposin."