The Polymorphisms in the Vitamin D Receptor Gene and Disease Severity in Sickle Cell Disease

DOI: 10.4236/abc.2015.51003   PDF   HTML   XML   2,769 Downloads   3,338 Views  

Abstract

Vitamin D is important in multiple aspects of health and its effects are mediated through the Vitamin D Receptor (VDR). We wanted to test the hypothesis that specific haplotypes of the VDR gene are associated with markers of disease severity, inflammation and bone health in Sickle Cell Disease (SCD). Genotyping was performed on DNA specimens from 1141 study participants in the NIH-funded Silent Infarct Transfusion (SIT) trial. We used the clinical and laboratory data to create separate endothelial dysfunction, vaso-occlusive severity scores and phenotype variables. Seventy-nine Single Nucleotide Polymorphisms (SNP) in the VDR gene and three associated genes—CYP27B1, VD binding protein, retinoid X receptor, were evaluated. The discovery cohort individuals had VDR haplotype information from a prior Genome-Wide Association Study (GWAS). The validation cohort was analyzed for SNPs that were significant in the discovery cohort. The pheno-type data were obtained from the demographic and clinical information of the participants, and were used to create the severity scores, vaso-occlusive score, endothelial dysfunction severity, and overall severity score. Potential gene-gene interactions were analyzed for prediction of disease severity within each severity score. Two SNPs were associated with the overall severity score, 3 SNPs with the endothelial dysfunction severity score and 4 SNPs with the vaso-occlusive severity score. After permutation testing to correct for multiple comparisons, only one of the associations remained significant. SNP rs7965281 was found to be associated with the endothelial dysfunction severity score and remained significant after correcting for multiple comparisons using permutation testing. In the validation cohort, that SNP was again tested for association with each of the severity scores. There was no association with the endothelial or the overall severity score but a trend towards association with the vaso-occlusive severity score (p = 0.02). None of the known functional polymorphisms in the VDR gene were found to have an association with severity in sickle cell disease. Further work analyzing for gene-gene interaction using the same significant SNPs remains to be done in association with inflammatory markers and measure of bone health. Those studies may provide insight on the contribution of VDR polymorphisms to sickle cell disease severity.

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Clay, E. , Motsinger-Reif, A. , Hoskins, J. , Veit, L. , Calikoglu, A. and Redding-Lallinger, R. (2015) The Polymorphisms in the Vitamin D Receptor Gene and Disease Severity in Sickle Cell Disease. Advances in Biological Chemistry, 5, 24-33. doi: 10.4236/abc.2015.51003.

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1] Fixler, J. and Styles, L. (2002) Sickle Cell Disease. Pediatric Clinics of North America, 49, 1193-210, vi.
http://dx.doi.org/10.1016/S0031-3955(02)00089-5
[2] Buison, A.M., Kawchak, D.A., Schall, J., Ohene-Frempong, K., et al. (2004) Low Vitamin D Status in Children with Sickle Cell Disease; Osteopenia and Vitamin D Deficiency in Children with Sickle Cell Disease. Journal of Pediatrics, 145, 622-627.
http://dx.doi.org/10.1016/j.jpeds.2004.06.055
[3] Reed, J.D., Redding-Lallinger, R. and Orringer, E.P. (1987) Nutrition and Sickle Cell Disease. American Journal of Hematology, 24, 441-455.
http://dx.doi.org/10.1002/ajh.2830240416
[4] Adewoye, A.H., Chen, T.C., Ma, Q., McMahon, L., Mathieu, J., Malabanan, A., et al. (2008) Sickle Cell Bone Disease: Response to Vitamin D and Calcium. American Journal of Hematology, 83, 271-274.
http://dx.doi.org/10.1002/ajh.21085
[5] Valdivielso, J.M. and Fernandez, E. (2006) Vitamin D Receptor Polymorphisms and Diseases. Clinica Chimica Acta, 371, 1-12.
http://dx.doi.org/10.1016/j.cca.2006.02.016
[6] Bouillon, R., Norman, A.W. and Lips, P. (2007) Vitamin D Deficiency. New England Journal of Medicine, 357, 1980-1981.
http://dx.doi.org/10.1056/NEJMc072359
[7] Rovner, A.J., Stallings, V.A., Kawchak, D.A., Schall, J.I., Ohene-Frempong, K. and Zemel, B.S. (2008) High Risk of Vitamin D Deficiency in Children with Sickle Cell Disease. Journal of the American Dietetic Association, 108, 1512-1516.
http://dx.doi.org/10.1016/j.jada.2008.06.433
[8] Uitterlinden, A.G., Fang, Y., Van Meurs, J.B., Pols, H.A. and Van Leeuwen, J.P. (2004) Genetics and Biology of Vitamin D Receptor Polymorphisms. Gene, 338, 143-156.
http://dx.doi.org/10.1016/j.gene.2004.05.014
[9] Kato, G.J., Gladwin, M.T. and Steinberg, M.H. (2007) Deconstruction Sickle Cell Disease: Reappraisal of the Role of Hemolysis in the Development of Clinical Subphenotypes. Blood Reviews, 21, 37-47.
http://dx.doi.org/10.1016/j.blre.2006.07.001
[10] Lou, X.Y., Chen, G.B., Yan, L., Ma, J.Z., Zhu, J., Elston, R.C., et al. (2007) A Generalized Combinatorial Approach for Detecting Gene-by-Gene and Gene-by-Environment Interactions with Application to Nicotine Dependence. American Journal of Human Genetics, 80, 1125-1137.
http://dx.doi.org/10.1086/518312
[11] Good, P. (2001) Extensions of the Concept of Exchangeability and Their Applications. Journal of Modern Applied Statistical Methods, 1, 243-247.
[12] Lou, X.Y., Chen, G.B., Yan, L., Ma, J.Z., Zhu, J., Elston, R.C. and Li, M.D. (2007) A Generalized Combinatorial Approach for Detecting Gene by Gene and Gene by environment Interactions with Application to Nicotine Dependence. American Journal of Human Genetics, 80, 1125-1137.
http://dx.doi.org/10.1086/518312
[13] Orlow, I., Roy, P., Reiner, A.S., Yoo, S., Patel, H., Paine, S., et al. (2011) Vitamin D Receptor Polymorphisms in Patients with Cutaneous Melanoma. International Journal of Cancer, 130, 405-418.
http://dx.doi.org/10.1002/ijc.26023

  
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