JOURNAL ARTICLE
RESEARCH SUPPORT, NON-U.S. GOV'T
RESEARCH SUPPORT, U.S. GOV'T, P.H.S.
Add like
Add dislike
Add to saved papers

Niemann-Pick disease: a frequent missense mutation in the acid sphingomyelinase gene of Ashkenazi Jewish type A and B patients.

Although the A and B subtypes of Niemann-Pick disease (NPD) both result from the deficient activity of acid sphingomyelinase (ASM; sphingomyelin cholinephosphohydrolase, EC 3.1.4.12) and the lysosomal accumulation of sphingomyelin, they have remarkably distinct phenotypes. Type A disease is a fatal neurodegenerative disorder of infancy, whereas type B disease has no neurologic manifestations and is characterized primarily by reticuloendothelial involvement and survival into adulthood. Both disorders are more frequent among individual of Ashkenazi Jewish ancestry than in the general population. The recent isolation and characterization of cDNA and genomic sequences encoding ASM has facilitated investigation of the molecular lesions causing the NPD subtypes. Total RNA was reverse-transcribed, and the ASM cDNA from an Ashkenazi Jewish type A patient was specifically amplified by the polymerase chain reaction (PCR). Molecular analysis of the PCR products revealed a G----T transversion of nucleotide 1487, which occurred at a CpG dinucleotide and predicted an Arg----Leu substitution in residue 496. Hybridization of PCR-amplified genomic DNA with allele-specific oligonucleotides indicated that the proband was homoallelic for the Arg----Leu substitution and that both parents and several other relatives were heterozygous. This mutation was detected in 32% (10 of 31) of the Ashkenazi Jewish NPD type A alleles studied and occurred in only 5.6% (2 of 36) of ASM alleles from non-Jewish type A patients. Of interest, the Arg----Leu substitution occurred in one of the ASM alleles from the two Ashkenazi Jewish NPD type B patients studied and in none of the ASM alleles of 15 non-Jewish type B patients. In contrast, the mutation was not present in 180 ASM alleles from normal individuals of Ashkenazi Jewish descent. These findings identify a frequent missense mutation among NPD patients of Ashkenazi Jewish ancestry that results in neuronopathic type A disease when homoallelic and can result in the nonneuronopathic type B phenotype when heteroallelic. The identification of this ASM mutation in Ashkenazi Jewish patients should facilitate the prevention of NPD in this population by carrier detection with molecular diagnostic techniques.

Full text links

We have located links that may give you full text access.
Can't access the paper?
Try logging in through your university/institutional subscription. For a smoother one-click institutional access experience, please use our mobile app.

For the best experience, use the Read mobile app

Mobile app image

Get seemless 1-tap access through your institution/university

For the best experience, use the Read mobile app

All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.

By using this service, you agree to our terms of use and privacy policy.

Your Privacy Choices Toggle icon

You can now claim free CME credits for this literature searchClaim now

Get seemless 1-tap access through your institution/university

For the best experience, use the Read mobile app