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Sphingomyelin phosphodiesterase-1 (SMPD1) coding variants do not contribute to low levels of high-density lipoprotein cholesterol.

ABSTRACT: BACKGROUND: Niemann-Pick disease type A and B is caused by a deficiency of acid sphingomyelinase due to mutations in the sphingomyelin phosphodiesterase-1 (SMPD1) gene. In Niemann-Pick patients, SMPD1 gene defects are reported to be associated with a severe reduction in plasma high-density lipoprotein (HDL) cholesterol. METHODS: Two common coding polymorphisms in the SMPD1 gene, the G1522A (G508R) and a hexanucleotide repeat sequence within the signal peptide region, were investigated in 118 unrelated subjects of French Canadian descent with low plasma levels of HDL-cholesterol (< 5th percentile for age and gender-matched subjects). Control subjects (n = 230) had an HDL-cholesterol level > the 25th percentile. RESULTS: For G1522A the frequency of the G and A alleles were 75.2% and 24.8% respectively in controls, compared to 78.6% and 21.4% in subjects with low HDL-cholesterol (p = 0.317). The frequency of 6 and 7 hexanucleotide repeats was 46.2% and 46.6% respectively in controls, compared to 45.6% and 49.1% in subjects with low HDL-cholesterol (p = 0.619). Ten different haplotypes were observed in cases and controls. Overall haplotype frequencies in cases and controls were not significantly different. CONCLUSION: These results suggest that the two common coding variants at the SMPD1 gene locus are not associated with low HDL-cholesterol levels in the French Canadian population.

SUBMITTER: Dastani Z

PROVIDER: S-EPMC2241771 | biostudies-other | 2007

REPOSITORIES: biostudies-other

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Sphingomyelin phosphodiesterase-1 (SMPD1) coding variants do not contribute to low levels of high-density lipoprotein cholesterol.

Dastani Zari Z Ruel Isabelle L IL Engert James C JC Genest Jacques J Marcil Michel M

BMC medical genetics 20071218

<h4>Background</h4>Niemann-Pick disease type A and B is caused by a deficiency of acid sphingomyelinase due to mutations in the sphingomyelin phosphodiesterase-1 (SMPD1) gene. In Niemann-Pick patients, SMPD1 gene defects are reported to be associated with a severe reduction in plasma high-density lipoprotein (HDL) cholesterol.<h4>Methods</h4>Two common coding polymorphisms in the SMPD1 gene, the G1522A (G508R) and a hexanucleotide repeat sequence within the signal peptide region, were investigat ...[more]

PMID: 18088425

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Sphingomyelin phosphodiesterase-1 (SMPD1) coding variants do not contribute to low levels of high-density lipoprotein cholesterol.

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Sphingomyelin phosphodiesterase-1 (SMPD1) coding variants do not contribute to low levels of high-density lipoprotein cholesterol.

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