Abstract
Background: Smith-Lemli-Opitz syndrome (MIM 270400) is an autosomal recessive malformation and mental retardation syndrome that ranges in clinical severity from minimal dysmorphism and mild mental retardation to severe congenital anomalies and intrauterine death. Smith-Lemli-Opitz syndrome is caused by mutations in the Δ7 sterol-reductase gene (DHCR7; EC 1.3.1.21), which impair endogenous cholesterol biosynthesis and make the growing embryo dependent on exogenous (maternal) sources of cholesterol. We have investigated whether apolipoprotein E, a major component of the cholesterol transport system in human beings, is a modifier of the clinical severity of Smith-Lemli-Opitz syndrome.
Method: Common apo E, DHCR7, and LDLR genotypes were determined in 137 biochemically characterised patients with Smith-Lemli-Opitz syndrome and 59 of their parents.
Results: There was a significant correlation between patients' clinical severity scores and maternal apo E genotypes (p = 0.028) but not between severity scores and patients' or paternal apo E genotypes. In line with their effects on serum cholesterol levels, the maternal apo ϵ2 genotypes were associated with a severe Smith-Lemli-Opitz syndrome phenotype, whereas apo E genotypes without the ϵ2 allele were associated with a milder phenotype. The correlation of maternal apo E genotype with disease severity persisted after stratification for DHCR7 genotype. There was no association of Smith-Lemli-Opitz syndrome severity with LDLR gene variation.
Conclusions: These results suggest that the efficiency of cholesterol transport from the mother to the embryo is affected by the maternal apo E genotype and extend the role of apo E and its disease associations to modulation of embryonic development and malformations.
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Selected References
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- Chiang C., Litingtung Y., Lee E., Young K. E., Corden J. L., Westphal H., Beachy P. A. Cyclopia and defective axial patterning in mice lacking Sonic hedgehog gene function. Nature. 1996 Oct 3;383(6599):407–413. doi: 10.1038/383407a0. [DOI] [PubMed] [Google Scholar]
- Cooper Michael K., Wassif Christopher A., Krakowiak Patrycja A., Taipale Jussi, Gong Ruoyu, Kelley Richard I., Porter Forbes D., Beachy Philip A. A defective response to Hedgehog signaling in disorders of cholesterol biosynthesis. Nat Genet. 2003 Mar 24;33(4):508–513. doi: 10.1038/ng1134. [DOI] [PubMed] [Google Scholar]
- Cunniff C., Kratz L. E., Moser A., Natowicz M. R., Kelley R. I. Clinical and biochemical spectrum of patients with RSH/Smith-Lemli-Opitz syndrome and abnormal cholesterol metabolism. Am J Med Genet. 1997 Jan 31;68(3):263–269. [PubMed] [Google Scholar]
- Farese R. V., Jr, Herz J. Cholesterol metabolism and embryogenesis. Trends Genet. 1998 Mar;14(3):115–120. doi: 10.1016/s0168-9525(97)01377-2. [DOI] [PubMed] [Google Scholar]
- Farese R. V., Jr, Ruland S. L., Flynn L. M., Stokowski R. P., Young S. G. Knockout of the mouse apolipoprotein B gene results in embryonic lethality in homozygotes and protection against diet-induced hypercholesterolemia in heterozygotes. Proc Natl Acad Sci U S A. 1995 Feb 28;92(5):1774–1778. doi: 10.1073/pnas.92.5.1774. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fitzky B. U., Witsch-Baumgartner M., Erdel M., Lee J. N., Paik Y. K., Glossmann H., Utermann G., Moebius F. F. Mutations in the Delta7-sterol reductase gene in patients with the Smith-Lemli-Opitz syndrome. Proc Natl Acad Sci U S A. 1998 Jul 7;95(14):8181–8186. doi: 10.1073/pnas.95.14.8181. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Göritz Christian, Mauch Daniela H., Nägler Karl, Pfrieger Frank W. Role of glia-derived cholesterol in synaptogenesis: new revelations in the synapse-glia affair. J Physiol Paris. 2002 Apr-Jun;96(3-4):257–263. doi: 10.1016/s0928-4257(02)00014-1. [DOI] [PubMed] [Google Scholar]
- Haddy Nadia, De Bacquer Dirk, Chemaly Marianne Mansour, Maurice Mickaël, Ehnholm Christian, Evans Alun, Sans Susanna, Do Carmo Martins Maria, De Backer Guy, Siest Gérard. The importance of plasma apolipoprotein E concentration in addition to its common polymorphism on inter-individual variation in lipid levels: results from Apo Europe. Eur J Hum Genet. 2002 Dec;10(12):841–850. doi: 10.1038/sj.ejhg.5200864. [DOI] [PubMed] [Google Scholar]
- Herz J., Willnow T. E., Farese R. V., Jr Cholesterol, hedgehog and embryogenesis. Nat Genet. 1997 Feb;15(2):123–124. doi: 10.1038/ng0297-123. [DOI] [PubMed] [Google Scholar]
- Irons M., Elias E. R., Salen G., Tint G. S., Batta A. K. Defective cholesterol biosynthesis in Smith-Lemli-Opitz syndrome. Lancet. 1993 May 29;341(8857):1414–1414. doi: 10.1016/0140-6736(93)90983-n. [DOI] [PubMed] [Google Scholar]
- Kelley R. I. Diagnosis of Smith-Lemli-Opitz syndrome by gas chromatography/mass spectrometry of 7-dehydrocholesterol in plasma, amniotic fluid and cultured skin fibroblasts. Clin Chim Acta. 1995 Apr 30;236(1):45–58. doi: 10.1016/0009-8981(95)06038-4. [DOI] [PubMed] [Google Scholar]
- Kelley R. I., Hennekam R. C. The Smith-Lemli-Opitz syndrome. J Med Genet. 2000 May;37(5):321–335. doi: 10.1136/jmg.37.5.321. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kratz L. E., Kelley R. I. Prenatal diagnosis of the RSH/Smith-Lemli-Opitz syndrome. Am J Med Genet. 1999 Feb 19;82(5):376–381. [PubMed] [Google Scholar]
- Lin D. S., Pitkin R. M., Connor W. E. Placental transfer of cholesterol into the human fetus. Am J Obstet Gynecol. 1977 Aug 1;128(7):735–739. doi: 10.1016/0002-9378(77)90713-x. [DOI] [PubMed] [Google Scholar]
- Mahley R. W. Apolipoprotein E: cholesterol transport protein with expanding role in cell biology. Science. 1988 Apr 29;240(4852):622–630. doi: 10.1126/science.3283935. [DOI] [PubMed] [Google Scholar]
- Mahley R. W., Rall S. C., Jr Apolipoprotein E: far more than a lipid transport protein. Annu Rev Genomics Hum Genet. 2000;1:507–537. doi: 10.1146/annurev.genom.1.1.507. [DOI] [PubMed] [Google Scholar]
- Mauch D. H., Nägler K., Schumacher S., Göritz C., Müller E. C., Otto A., Pfrieger F. W. CNS synaptogenesis promoted by glia-derived cholesterol. Science. 2001 Nov 9;294(5545):1354–1357. doi: 10.1126/science.294.5545.1354. [DOI] [PubMed] [Google Scholar]
- McConihay J. A., Honkomp A. M., Granholm N. A., Woollett L. A. Maternal high density lipoproteins affect fetal mass and extra-embryonic fetal tissue sterol metabolism in the mouse. J Lipid Res. 2000 Mar;41(3):424–432. [PubMed] [Google Scholar]
- McConihay J. A., Horn P. S., Woollett L. A. Effect of maternal hypercholesterolemia on fetal sterol metabolism in the Golden Syrian hamster. J Lipid Res. 2001 Jul;42(7):1111–1119. [PubMed] [Google Scholar]
- Nadeau J. H. Modifier genes in mice and humans. Nat Rev Genet. 2001 Mar;2(3):165–174. doi: 10.1038/35056009. [DOI] [PubMed] [Google Scholar]
- Nezarati Marjan M., Loeffler Judith, Yoon Grace, MacLaren Linda, Fung Ernest, Snyder Floyd, Utermann Gerd, Graham Gail E. Novel mutation in the Delta-sterol reductase gene in three Lebanese sibs with Smith-Lemli-Opitz (RSH) syndrome. Am J Med Genet. 2002 Jun 15;110(2):103–108. doi: 10.1002/ajmg.10367. [DOI] [PubMed] [Google Scholar]
- Overbergh L., Lorent K., Torrekens S., Van Leuven F., Van den Berghe H. Expression of mouse alpha-macroglobulins, lipoprotein receptor-related protein, LDL receptor, apolipoprotein E, and lipoprotein lipase in pregnancy. J Lipid Res. 1995 Aug;36(8):1774–1786. [PubMed] [Google Scholar]
- Roessler E., Belloni E., Gaudenz K., Jay P., Berta P., Scherer S. W., Tsui L. C., Muenke M. Mutations in the human Sonic Hedgehog gene cause holoprosencephaly. Nat Genet. 1996 Nov;14(3):357–360. doi: 10.1038/ng1196-357. [DOI] [PubMed] [Google Scholar]
- Roses A. D. Apolipoprotein E alleles as risk factors in Alzheimer's disease. Annu Rev Med. 1996;47:387–400. doi: 10.1146/annurev.med.47.1.387. [DOI] [PubMed] [Google Scholar]
- SMITH D. W., LEMLI L., OPITZ J. M. A NEWLY RECOGNIZED SYNDROME OF MULTIPLE CONGENITAL ANOMALIES. J Pediatr. 1964 Feb;64:210–217. doi: 10.1016/s0022-3476(64)80264-x. [DOI] [PubMed] [Google Scholar]
- Steinmetz A., Thiemann E., Czekelius P., Kaffarnik H. Polymorphism of apolipoprotein E influences levels of serum apolipoproteins E and B in the human neonate. Eur J Clin Invest. 1989 Aug;19(4):390–394. doi: 10.1111/j.1365-2362.1989.tb00247.x. [DOI] [PubMed] [Google Scholar]
- Tint G. S., Irons M., Elias E. R., Batta A. K., Frieden R., Chen T. S., Salen G. Defective cholesterol biosynthesis associated with the Smith-Lemli-Opitz syndrome. N Engl J Med. 1994 Jan 13;330(2):107–113. doi: 10.1056/NEJM199401133300205. [DOI] [PubMed] [Google Scholar]
- Utermann G. Apolipoprotein E polymorphism in health and disease. Am Heart J. 1987 Feb;113(2 Pt 2):433–440. doi: 10.1016/0002-8703(87)90610-7. [DOI] [PubMed] [Google Scholar]
- Utermann G., Hees M., Steinmetz A. Polymorphism of apolipoprotein E and occurrence of dysbetalipoproteinaemia in man. Nature. 1977 Oct 13;269(5629):604–607. doi: 10.1038/269604a0. [DOI] [PubMed] [Google Scholar]
- Wassif C. A., Maslen C., Kachilele-Linjewile S., Lin D., Linck L. M., Connor W. E., Steiner R. D., Porter F. D. Mutations in the human sterol delta7-reductase gene at 11q12-13 cause Smith-Lemli-Opitz syndrome. Am J Hum Genet. 1998 Jul;63(1):55–62. doi: 10.1086/301936. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Waterham H. R., Wijburg F. A., Hennekam R. C., Vreken P., Poll-The B. T., Dorland L., Duran M., Jira P. E., Smeitink J. A., Wevers R. A. Smith-Lemli-Opitz syndrome is caused by mutations in the 7-dehydrocholesterol reductase gene. Am J Hum Genet. 1998 Aug;63(2):329–338. doi: 10.1086/301982. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Willnow T. E., Hilpert J., Armstrong S. A., Rohlmann A., Hammer R. E., Burns D. K., Herz J. Defective forebrain development in mice lacking gp330/megalin. Proc Natl Acad Sci U S A. 1996 Aug 6;93(16):8460–8464. doi: 10.1073/pnas.93.16.8460. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Witsch-Baumgartner M., Fitzky B. U., Ogorelkova M., Kraft H. G., Moebius F. F., Glossmann H., Seedorf U., Gillessen-Kaesbach G., Hoffmann G. F., Clayton P. Mutational spectrum in the Delta7-sterol reductase gene and genotype-phenotype correlation in 84 patients with Smith-Lemli-Opitz syndrome. Am J Hum Genet. 2000 Feb;66(2):402–412. doi: 10.1086/302760. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wyne K. L., Woollett L. A. Transport of maternal LDL and HDL to the fetal membranes and placenta of the Golden Syrian hamster is mediated by receptor-dependent and receptor-independent processes. J Lipid Res. 1998 Mar;39(3):518–530. [PubMed] [Google Scholar]