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Combined saposin deficiency: A rare occurrence.

ABSTRACT: Combined saposin deficiency (OMIM #611721), an exceedingly rare lysosomal storage disorder, is caused by a mutation in the gene PSAP. This gene encodes a protein, prosaposin, that cleaves into four constituent proteins, each of which has a role as a cofactor for the enzymes whose deficiency results in Krabbe disease, metachromatic leukodystrophy, Gaucher disease, and Farber disease, respectively. Intact prosaposin itself is essential for neuronal survival. The typical manifestation of combined saposin deficiency is of severe neurological features in the neonatal period, hepatosplenomegaly, thrombocytopenia, and early death. We report, to the best of our knowledge, the first Indian case with these clinical manifestations and confirmation by genetic and enzymatic testing.

SUBMITTER: Bhat V

PROVIDER: S-EPMC10037043 | biostudies-literature | 2023 Mar-Apr

REPOSITORIES: biostudies-literature

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Combined saposin deficiency: A rare occurrence.

Bhat Vivek V Thergaonkar R W RW Thakur Manisha M Rajkamal T T

Medical journal, Armed Forces India 20210512 2

Combined saposin deficiency (OMIM #611721), an exceedingly rare lysosomal storage disorder, is caused by a mutation in the gene <i>PSAP</i>. This gene encodes a protein, prosaposin, that cleaves into four constituent proteins, each of which has a role as a cofactor for the enzymes whose deficiency results in Krabbe disease, metachromatic leukodystrophy, Gaucher disease, and Farber disease, respectively. Intact prosaposin itself is essential for neuronal survival. The typical manifestation of com ...[more]

PMID: 36969110

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