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Improved sensitivity of an acid sphingomyelinase activity assay using a C6:0 sphingomyelin substrate.

ABSTRACT: Short-chain C6-sphingomyelin is an artificial substrate that was used in an acid sphingomyelinase activity assay for a pilot screening study of patients with Niemann-Pick disease types A and B. Using previously published multiplex and single assay conditions, normal acid sphingomyelinase activity levels (i.e. false negative results) were observed in two sisters with Niemann-Pick B who were compound heterozygotes for two missense mutations, p.C92W and p.P184L, in the SMPD1 gene. Increasing the sodium taurocholate detergent concentration in the assay buffer lowered the activity levels of these two patients into the range observed with other patients with clear separation from normal controls.

SUBMITTER: Chuang WL

PROVIDER: S-EPMC4750609 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Improved sensitivity of an acid sphingomyelinase activity assay using a C6:0 sphingomyelin substrate.

Chuang Wei-Lien WL Pacheco Joshua J Cooper Samantha S Kingsbury Jonathan S JS Hinds John J Wolf Pavlina P Oliva Petra P Keutzer Joan J Cox Gerald F GF Zhang Kate K

Molecular genetics and metabolism reports 20150417

Short-chain C6-sphingomyelin is an artificial substrate that was used in an acid sphingomyelinase activity assay for a pilot screening study of patients with Niemann-Pick disease types A and B. Using previously published multiplex and single assay conditions, normal acid sphingomyelinase activity levels (i.e. false negative results) were observed in two sisters with Niemann-Pick B who were compound heterozygotes for two missense mutations, p.C92W and p.P184L, in the SMPD1 gene. Increasing the so ...[more]

PMID: 26937397

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