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Much of the work carried out by DTT is in support of the National Toxicology Program (NTP), an interagency partnership of the Food and Drug Administration, National Institute for Occupational Safety and Health, and NIEHS.

B. Alex Merrick, Ph.D., is a Molecular Toxicologist who joined the Division of Translational Toxicology (DTT) in 2010. He was Acting Branch Chief of the Mechanistic Toxicology Branch in DTT from 2023 to 2019. Prior to MTB, he headed the Molecular Toxicology and Genomics Group from 2019 to 2010 in the Biomolecular Screening Branch (BSB) in DTT. His responsibilities have included identifying key signaling pathways and transcripts altered by environmental toxicants and participating in the Tox21 collaboration among the DTT, the NIH National Center for Advancing Translational Sciences (NCATS), the Environmental Protection Agency's National Center for Computational Toxicology (NCCT) and the Food and Drug Administration (FDA). He is especially interested in performing molecular analysis in DTT archival tissues and plasma to discover gene expression, epigenetic and mutational signatures from chemical toxicology studies. Collaborative work with the Cellular and Molecular Pathology Branch (CMPB) aimed to use NTP archival research for further pathological insight, better understand mechanisms of chemical toxicity and contribution to predictive models of toxicity and chemical prioritization as a complementary effort to the Tox21 high throughput screening program. He has initiated and managed contracts in Bioinformatics and NextGen Sequencing (NGS). NGS-based projects help DTT better evaluate the transcriptomic and genomic alterations in chemically-exposed tissues by creating differential transcript profiles that include splice variants, low copy transcripts and non-coding mRNA's. More recent interests include Omics analysis of blood-borne circulating cell free DNA (ccfDNA) and exosomal contents in developing biomarker panels of toxicity and chemical exposure.

Before joining the DTT, Merrick was head of the Proteomics Group within the Division of Intramural Research's (DIR) National Center for Toxicogenomics. His group performed protein and gene expression profiling of hepatoxic agents to identify mechanisms of liver injury, with a special interest in p53 biology and chemical carcinogenesis.

Merrick received his Ph.D. in 1984 at the University of Nebraska Medical Center in Omaha, performing post-doctoral work in the Biology Division at Oak Ridge National Laboratory. He headed the Hepatotoxicology section at the US EPA in Cincinnati, OH from 1985 to 1988 before joining NIEHS in 1988. In addition, he served for over 20 years as an adjunct Associate Professor in the Department of Environmental and Molecular Toxicology at NC State University.

Recent Publications

  1. Foley JF, Elgart B, Phadke D, Mav D, Tripodi I, Clausen N, Weick M, Gladwell W, Gerrish K, Shah R, Merrick BA. 2023. Whole exome and transcript profiling of liver following AFB1 exposure in rats. J Appl Toxicol. doi: 10.1002/jat.4463. [Abstract Foley JF, Elgart B, Phadke D, Mav D, Tripodi I, Clausen N, Weick M, Gladwell W, Gerrish K, Shah R, Merrick BA. 2023. Whole exome and transcript profiling of liver following AFB1 exposure in rats. J Appl Toxicol. doi: 10.1002/jat.4463.]
  2. Qu W, Yan Y, Gerrish K, Scappini E, Tucker CJ, Dixon D, Merrick BA. 2023. Chronic PFOA exposure in vitro causes acquisition of multiple tumor cell characteristics in rat liver cells. Toxicol In Vitro. 89:105577. doi: 10.1016/j.tiv.2023.105577. [Abstract Qu W, Yan Y, Gerrish K, Scappini E, Tucker CJ, Dixon D, Merrick BA. 2023. Chronic PFOA exposure in vitro causes acquisition of multiple tumor cell characteristics in rat liver cells. Toxicol In Vitro. 89:105577. doi: 10.1016/j.tiv.2023.105577.]
  3. Dunnick JK, Pandiri AR, Herbert R, Shockley KR, Mav D, Shah RR, Merrick BA. 2022. Single nucleotide polymorphism patterns associated with a cancer resistant phenotype. Exptl Molec Pathol. 128:104812. doi: 10.1016/j.yexmp.2022.104812. [Abstract Dunnick JK, Pandiri AR, Herbert R, Shockley KR, Mav D, Shah RR, Merrick BA. 2022. Single nucleotide polymorphism patterns associated with a cancer resistant phenotype. Exptl Molec Pathol. 128:104812. doi: 10.1016/j.yexmp.2022.104812.]
  4. Tandon A, Howard B, Ramaiahgari S, Maharana A, Ferguson S, Shah R, Merrick BA. 2022. Deep Learning Image Analysis of High-Throughput Toxicology Assay Images. SLAS Discov. 27(1):29-38. doi: 10.1016/j.slasd.2021.10.014. [Abstract Tandon A, Howard B, Ramaiahgari S, Maharana A, Ferguson S, Shah R, Merrick BA. 2022. Deep Learning Image Analysis of High-Throughput Toxicology Assay Images. SLAS Discov. 27(1):29-38. doi: 10.1016/j.slasd.2021.10.014.]
  5. Foley JF, Elgart B, Merrick BA, Phadke DP, Shah RR, Cook ME, Malphurs JA, Solomon GG, Fessler MB, Humble MC, Miller FW and Gerrish KE. 2021. Whole genome sequencing from low input circulating cell-free DNA in normal human subjects. Physiol Reports. 9(15): e14993. doi: 10.14814/phy2.14993. [Abstract Foley JF, Elgart B, Merrick BA, Phadke DP, Shah RR, Cook ME, Malphurs JA, Solomon GG, Fessler MB, Humble MC, Miller FW and Gerrish KE. 2021. Whole genome sequencing from low input circulating cell-free DNA in normal human subjects. Physiol Reports. 9(15): e14993. doi: 10.14814/phy2.14993.]
  6. Merrick BA, Phadke DP, Bostrom MA, Shah RR, Wright GM, Wang X, Gordon O, Pelch KE, Auerbach SS, Paules RS, DeVito MJ, Waalkes MP, Tokar EJ. KRAS-retroviral fusion transcripts and gene amplification in arsenic-transformed, human prostate CAsE-PE cancer cells. Toxicol Appl Pharmacol 2020. doi: 10.1016/j.taap.2020.115017 [Online 25 April 2020]. [Abstract Merrick BA, Phadke DP, Bostrom MA, Shah RR, Wright GM, Wang X, Gordon O, Pelch KE, Auerbach SS, Paules RS, DeVito MJ, Waalkes MP, Tokar EJ. KRAS-retroviral fusion transcripts and gene amplification in arsenic-transformed, human prostate CAsE-PE cancer cells. Toxicol Appl Pharmacol 2020. doi: 10.1016/j.taap.2020.115017 [Online 25 April 2020].]
  7. Grimm SA, Shimbo T, Takaku M, Thomas JW, Auerbach SS, Bennett B, Bucher JR, Burkholder A, Day F, Du Y, Due Y, French JE, Li J, Merrick BA, Tice RR, Wang T, Xu X, Bushel P, Fargo DC, Mullikin JC and Wade PA. (2019). Genetics, sex and life experience-based influences on DNA methylation in mice. Nature Comm. 10(1):305. [Abstract Grimm SA, Shimbo T, Takaku M, Thomas JW, Auerbach SS, Bennett B, Bucher JR, Burkholder A, Day F, Du Y, Due Y, French JE, Li J, Merrick BA, Tice RR, Wang T, Xu X, Bushel P, Fargo DC, Mullikin JC and Wade PA. (2019). Genetics, sex and life experience-based influences on DNA methylation in mice. Nature Comm. 10(1):305.]
  8. Aloor J, Azzam K, Guardiola J, Gowdy K, Madenspacher J, Gabor K, Mueller G, Lin W-C, Lowe J, Gruzdev A, Henderson M, Draper D, Merrick B, and Fessler M. (2019). Leucine-Rich Repeats and Calponin Homology containing 4 regulates the innate immune response. J. Biol. Chem. 294(6):1996-2018. [Abstract Aloor J, Azzam K, Guardiola J, Gowdy K, Madenspacher J, Gabor K, Mueller G, Lin W-C, Lowe J, Gruzdev A, Henderson M, Draper D, Merrick B, and Fessler M. (2019). Leucine-Rich Repeats and Calponin Homology containing 4 regulates the innate immune response. J. Biol. Chem. 294(6):1996-2018.]
  9. Balik-Meisner MR, Phadke D, Mav D, Everett LJ, Shah RR, Shepard PJ, Tal T, Merrick BA, Paules RS. 2019. Development of a Zebrafish S1500+ Sentinel Gene Set for High-Throughput Transcriptomics. Zebrafish. 16(4):331-347. doi: 10.1089/zeb.2018.1720. [Abstract Balik-Meisner MR, Phadke D, Mav D, Everett LJ, Shah RR, Shepard PJ, Tal T, Merrick BA, Paules RS. 2019. Development of a Zebrafish S1500+ Sentinel Gene Set for High-Throughput Transcriptomics. Zebrafish. 16(4):331-347. doi: 10.1089/zeb.2018.1720.]
  10. Merrick BA. Next-generation sequencing data for use in risk assessment. 2019. Current opinion in toxicology. 18:18-26. doi: 10.1016/j.cotox.2019.02.010. [Abstract Merrick BA. Next-generation sequencing data for use in risk assessment. 2019. Current opinion in toxicology. 18:18-26. doi: 10.1016/j.cotox.2019.02.010.]
  11. Merrick BA, Phadke DP, Bostrom MA, Shah RR, Wright GM, Wang X, Pelch KE, Waalkes MP, Auerbach SS, Paules RS, DeVito MJ, Tokar EJ. 2019. Arsenite malignantly transforms human prostate epithelial cells in vitro by gene amplification of mutated KRAS. PLoS One. 14(4):e0215504. [Abstract Merrick BA, Phadke DP, Bostrom MA, Shah RR, Wright GM, Wang X, Pelch KE, Waalkes MP, Auerbach SS, Paules RS, DeVito MJ, Tokar EJ. 2019. Arsenite malignantly transforms human prostate epithelial cells in vitro by gene amplification of mutated KRAS. PLoS One. 14(4):e0215504.]
  12. Foley JF, Phadke DP, Hardy O, Hardy S, Miller V, Madan A, Howard K, Kruse K, Lord C, Ramaiahgari S, Solomon GG, Shah RR, Pandiri AR, Herbert RA, Sills RC and Merrick BA. (2018). Whole exome sequencing in the rat. BMC Genomics. 13:e0190992, 1-14. [Abstract Foley JF, Phadke DP, Hardy O, Hardy S, Miller V, Madan A, Howard K, Kruse K, Lord C, Ramaiahgari S, Solomon GG, Shah RR, Pandiri AR, Herbert RA, Sills RC and Merrick BA. (2018). Whole exome sequencing in the rat. BMC Genomics. 13:e0190992, 1-14.]
  13. Merrick BA, Chang JS, Bostrom MA, Phadke DP, Shah RR, Wang X, Gordon O and Wright, GM. (2018). HAfTs are novel lncRNA transcripts from aflatoxin exposure. PLoS One. 13(1): e0190992, 1-25. [Abstract Merrick BA, Chang JS, Bostrom MA, Phadke DP, Shah RR, Wang X, Gordon O and Wright, GM. (2018). HAfTs are novel lncRNA transcripts from aflatoxin exposure. PLoS One. 13(1): e0190992, 1-25.]
  14. Mav D, Shah RR, Howard BE, Auerbach SS, Bushel PR, Collins JB, Gerhold D, Judson RS, Karmaus AL, Maull E, Mendrick DL, Merrick BA, Sipes NS, Svoboda D and Paules RS. (2018). A hybrid gene selection approach to create the S1500+ targeted gene sets for use in high-throughput transcriptomics. PLoS One 13(2):e0191105, 1-19. [Abstract Mav D, Shah RR, Howard BE, Auerbach SS, Bushel PR, Collins JB, Gerhold D, Judson RS, Karmaus AL, Maull E, Mendrick DL, Merrick BA, Sipes NS, Svoboda D and Paules RS. (2018). A hybrid gene selection approach to create the S1500+ targeted gene sets for use in high-throughput transcriptomics. PLoS One 13(2):e0191105, 1-19.]
  15. Li R, Grimm SA, Mav D, Gu H, Djukovic D, Shah R, Merrick BA, Raftery D and Wade PA. (2018). Epigenetic memory of obesity predisposes to colorectal cancer. Cell Reports. 22(3): 624-637. [Abstract Li R, Grimm SA, Mav D, Gu H, Djukovic D, Shah R, Merrick BA, Raftery D and Wade PA. (2018). Epigenetic memory of obesity predisposes to colorectal cancer. Cell Reports. 22(3): 624-637.]