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Kirby D. Smith, Ph.D.

Photo of Dr. Kirby D. Smith, Ph.D.

Professor of Pediatrics

Contact for Research Inquiries

McKusick-Nathans Institute for Genetic Medicine
Johns Hopkins University
School of Medicine
Baltimore, MD 21205 map

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Dr. Kirby D. Smith is a professor of pediatrics at the Johns Hopkins University School of Medicine. His research focuses on genetic hemoglobinopathies and neurodegeneration. He is a researcher in the McKusick-Nathans Institute for Genetic Medicine.

He is currently studying X-linked adrenoleukodystrophy (X-ALD), a neurodegenerative disorder, and ALDP, the product of the gene defective in the disorder. more


  • Professor of Pediatrics

Departments / Divisions

Research & Publications

Research Summary

The severity of adult hemoglobinopathies can be moderated by the presence of red cells containing fetal hemoglobin (F-cells). The fraction of F-cells in adults varies over a 20 fold range. We have identified a locus (FCP) on the X-chromosome that accounts for 50% of this variation. The FCP gene has been mapped to a small (<1Mb) region of Xp and its physical isolation is in progress.

X-linked adrenoleukodystrophy (X-ALD) is a neurodegenerative disorder with variable phenotypic expression that is characterized by elevated very long chain fatty acids. However, the product of the gene defective in X-ALD (ALDP) is a membrane transporter and is not related to enzymes that activate or oxidize fatty acids. Using genetic anlyses, we have identified an autosomal gene that in part determines the phenotypic expression of X-ALD. We are examining the function of ALDP, determining the underlying pathophysiology of the various forms of X-ALD, searching for the autosomal modifying gene and investigating the possibility of pharmcological gene therapy for peroxisomal disorders.

Selected Publications

View all on Pubmed

Processed pseudogene insertions in somatic cells. Kazazian HH Jr. Mob DNA. 2014 Jul 2;5:20. doi: 10.1186/1759-8753-5-20.

In vitro screening for compounds that enhance human L1 mobilization. Terasaki N, Goodier JL, Cheung LE, Wang YJ, Kajikawa M, Kazazian HH Jr, Okada N. PLoS One. 2013 Sep 11;8(9):e74629. doi: 10.1371/journal.pone.0074629.

Modulation of LINE-1 and Alu/SVA retrotransposition by Aicardi-Gouti&egrave;res syndrome-related SAMHD1. Zhao K, Du J, Han X, Goodier JL, Li P, Zhou X, Wei W, Evans SL, Li L, Zhang W, Cheung LE, Wang G, Kazazian HH Jr, Yu XF. Cell Rep. 2013 Sep 26;4(6):1108-15. doi: 10.1016/j.celrep.2013.08.019.

Mapping the LINE1 ORF1 protein interactome reveals associated inhibitors of human retrotransposition. Goodier JL, Cheung LE, Kazazian HH Jr. Nucleic Acids Res. 2013 Aug;41(15):7401-19. doi: 10.1093/nar/gkt512. Epub 2013 Jun 9.

Enrichment of processed pseudogene transcripts in L1-ribonucleoprotein particles. Mandal PK, Ewing AD, Hancks DC, Kazazian HH Jr. Hum Mol Genet. 2013 Sep 15;22(18):3730-48. doi: 10.1093/hmg/ddt225. Epub 2013 May 21.

Singh K, Connors SL, Macklin EA, Smith KD, Fahey JW, Talalay P, Zimmerman AW. "Sulforaphane treatment of autism spectrum disorder (ASD)." Proc Natl Acad Sci U S A. 2014 Oct 28;111(43):15550-5. doi: 10.1073/pnas.1416940111. Epub 2014 Oct 13.

Brose RD, Shin G, McGuinness MC, Schneidereith T, Purvis S, Dong GX, Keefer J, Spencer F, Smith KD. "Activation of the stress proteome as a mechanism for small molecule therapeutics." Hum Mol Genet. 2012 Oct 1;21(19):4237-52. doi: 10.1093/hmg/dds247. Epub 2012 Jul 2.

Brose RD, Avramopoulos D, Smith KD. "SOD2 as a potential modifier of X-linked adrenoleukodystrophy clinical phenotypes." J Neurol. 2012 Jul;259(7):1440-7. doi: 10.1007/s00415-011-6371-8. Epub 2012 Jan 5.

Duggan PS, Siegel AW, Blass DM, Bok H, Coyle JT, Faden R, Finkel J, Gearhart JD, Greely HT, Hillis A, et al. "Unintended changes in cognition, mood, and behavior arising from cell-based interventions for neurological conditions: Ethical challenges." American Journal of Bioethics. 2009;9(5):31-36.

Regenberg A, Mathews DJH, Blass DM, Bok H, Coyle JT, Duggan P, Finkel J, Greely HT, Hillis A, Hoke A, et al. "Cell-based interventions for neurological conditions: Ethical challenges for early human trials." Neurology. 2008;71(4):288-293.

Academic Affiliations & Courses

Courses and Syllabi

  • Advanced Topics in Human Genetics (Course Co-director)
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