Mitchell Machiela, Sc.D., M.P.H.
Integrative Tumor Epidemiology Branch
9609 Medical Center Drive
Rockville, MD 20850
Dr. Mitchell Machiela’s research is focused on elucidating the role of germline variation and somatic mosaicism in cancer risk. He is leading studies of large-scale genetic mosaicism to investigate the causes of acquired mosaic alterations and their impact on cancer risk. He also conducts and analyzes genetic association studies to elucidate the underlying genetic architecture of different cancers (e.g. pediatric and common adult cancers).
Genetic mosaicism results from an acquired DNA mutation that is present in some of the body's cells but not in others. A person with mosaicism has a mixture of normal and mutated cells. Dr. Machiela has published findings that estimate the frequency and distribution of mosaicism in existing genotyped collections of blood and buccal DNA. He is utilizing an unparalleled set of genotype data – 200,000 DCEG samples, 500,000 genotyped samples from the UK Biobank, and a merged international mosaicism consortium of over 1 million samples – to expand the size and scope of his research on mosaicism and cancer risk.
Relatively little is known of the mechanisms that initiate and select for mosaic alterations. Results from previous work suggests inherited germline variation (e.g. at TCL1A) or environmental exposures (e.g. smoking) may predispose to mosaicism. Dr. Machiela is utilizing genotyped samples from the UK Biobank and other datasets to examine endogenous and exogenous factors influencing acquisition of detectible mosaicism.
Acquired mosaic alterations have abundant potential to inform cancer etiology and drive oncogenic change. Dr. Machiela has found evidence to suggest that mosaicism increases cancer risk for hematologic malignancies and select solid tumor subtypes. He will continue to examine the influence of mosaicism on cancer risk in various populations and tissue types.
Genetic Architecture of Cancer
Dr. Machiela and colleagues have published several genome-wide association studies (GWAS) of common adult cancers. He is working to better understand the genomic architecture of cancer by performing genetic association studies in pediatric cancers, expanding association studies to incorporate whole-exome/genome sequencing data, and combining data on germline and somatic variation to better understand cancer genetic etiology and improve risk prediction.
Pediatric cancers like Ewing sarcoma (ES) provide a unique opportunity to study a homogenous tumor with potentially larger genetic contribution to risk. Dr. Machiela is leading a GWAS on ES to identify susceptibility regions and elucidate the underlying genetic architecture of ES.
Dr. Machiela is also the creator of a web-based tool, LDlink, which interactively explores linkage disequilibrium across 1000 Genomes population groups. LDlink is tailored for investigators interested in mapping disease susceptibility loci by generating output linking correlated alleles and highlighting putative functional variants.
Dr. Machiela received his M.P.H. in epidemiology from the University of Michigan and his Sc.D. in epidemiology from the Harvard T.H. Chan School of Public Health. He joined the Laboratory of Translational Genomics as a postdoctoral fellow in 2012, and transitioned to the Laboratory of Genetic Susceptibility in 2015. In 2016, he was promoted to research fellow. He was appointed to the position of Earl Stadtman Tenure-Track Investigator in 2017. Dr. Machiela has received numerous awards for his work, including two DCEG Fellowship Achievement Awards and two awards for the DCEG Outstanding Research Paper by a Fellow.
Machiela MJ, Zhou W, Sampson JN, Dean MC, Jacobs KB, Black A, Brinton LA, Chang IS, Chen C, Chen C, Chen K, Cook LS, Crous Bou M, De Vivo I, Doherty J, Friedenreich CM, Gaudet MM, Haiman CA, Hankinson SE, Hartge P, Henderson BE, Hong YC, Hosgood HD 3rd, Hsiung CA, Hu W, Hunter DJ, Jessop L, Kim HN, Kim YH, Kim YT, Klein R, Kraft P, Lan Q, Lin D, Liu J, Le Marchand L, Liang X, Lissowska J, Lu L, Magliocco AM, Matsuo K, Olson SH, Orlow I, Park JY, Pooler L, Prescott J, Rastogi R, Risch HA, Schumacher F, Seow A, Setiawan VW, Shen H, Sheng X, Shin MH, Shu XO, VanDen Berg D, Wang JC, Wentzensen N, Wong MP, Wu C, Wu T, Wu YL, Xia L, Yang HP, Yang PC, Zheng W, Zhou B, Abnet CC, Albanes D, Aldrich MC, Amos C, Amundadottir LT, Berndt SI, Blot WJ, Bock CH, Bracci PM, Burdett L, Buring JE, Butler MA, Carreón T, Chatterjee N, Chung CC, Cook MB, Cullen M, Davis FG, Ding T, Duell EJ, Epstein CG, Fan JH, Figueroa JD, Fraumeni JF Jr, Freedman ND, Fuchs CS, Gao YT, Gapstur SM, Patiño-Garcia A, Garcia-Closas M, Gaziano JM, Giles GG, Gillanders EM, Giovannucci EL, Goldin L, Goldstein AM, Greene MH, Hallmans G, Harris CC, Henriksson R, Holly EA, Hoover RN, Hu N, Hutchinson A, Jenab M, Johansen C, Khaw KT, Koh WP, Kolonel LN, Kooperberg C, Krogh V, Kurtz RC, LaCroix A, Landgren A, Landi MT, Li D, Liao LM, Malats N, McGlynn KA, McNeill LH, McWilliams RR, Melin BS, Mirabello L, Peplonska B, Peters U, Petersen GM, Prokunina-Olsson L, Purdue M, Qiao YL, Rabe KG, Rajaraman P, Real FX, Riboli E, Rodríguez-Santiago B, Rothman N, Ruder AM, Savage SA, Schwartz AG, Schwartz KL, Sesso HD, Severi G, Silverman DT, Spitz MR, Stevens VL, Stolzenberg-Solomon R, Stram D, Tang ZZ, Taylor PR, Teras LR, Tobias GS, Viswanathan K, Wacholder S, Wang Z, Weinstein SJ, Wheeler W, White E, Wiencke JK, Wolpin BM, Wu X, Wunder JS, Yu K, Zanetti KA, Zeleniuch-Jacquotte A, Ziegler RG, de Andrade M, Barnes KC, Beaty TH, Bierut LJ, Desch KC, Doheny KF, Feenstra B, Ginsburg D, Heit JA, Kang JH, Laurie CA, Li JZ, Lowe WL, Marazita ML, Melbye M, Mirel DB, Murray JC, Nelson SC, Pasquale LR, Rice K, Wiggs JL, Wise A, Tucker M, Pérez-Jurado LA, Laurie CC, Caporaso NE, Yeager M, Chanock SJ. Characterization of large structural genetic mosaicism in human autosomes. Am J Hum Genet. 2015;96(3):487-97.
Machiela MJ, Chanock SJ. LDlink: a web-based application for exploring population-specific haplotype structure and linking correlated alleles of possible functional variants. Bioinformatics. 2015;31(21):3555-7.
Machiela MJ, Ho BM, Fisher VA, Hua X, Chanock SJ. Limited evidence that cancer susceptibility regions are preferential targets for somatic mutation. Genome Biol. 2015;16:193.
Zhou W, Machiela MJ, Freedman ND, Rothman N, Malats N, Dagnall C, Caporaso N, Teras LT, Gaudet MM, Gapstur SM, Stevens VL, Jacobs KB, Sampson J, Albanes D, Weinstein S, Virtamo J, Berndt S, Hoover RN, Black A, Silverman D, Figueroa J, Garcia-Closas M, Real FX, Earl J, Marenne G, Rodriguez-Santiago B, Karagas M, Johnson A, Schwenn M, Wu X, Gu J, Ye Y, Hutchinson A, Tucker M, Perez-Jurado LA, Dean M, Yeager M, Chanock SJ. Mosaic loss of chromosome Y is associated with common variation near TCL1A. Nat Genet. 2016;48(5):563-8.
Machiela MJ, Zhou W, Karlins E, Sampson JN, Freedman ND, Yang Q, Hicks B, Dagnall C, Hautman C, Jacobs KB, Abnet CC, Aldrich MC, Amos C, Amundadottir LT, Arslan AA, Beane-Freeman LE, Berndt SI, Black A, Blot WJ, Bock CH, Bracci PM, Brinton LA, Bueno-de-Mesquita HB, Burdett L, Buring JE, Butler MA, Canzian F, Carreón T, Chaffee KG, Chang IS, Chatterjee N, Chen C, Chen C, Chen K, Chung CC, Cook LS, Crous Bou M, Cullen M, Davis FG, De Vivo I, Ding T, Doherty J, Duell EJ, Epstein CG, Fan JH, Figueroa JD, Fraumeni JF, Friedenreich CM, Fuchs CS, Gallinger S, Gao YT, Gapstur SM, Garcia-Closas M, Gaudet MM, Gaziano JM, Giles GG, Gillanders EM, Giovannucci EL, Goldin L, Goldstein AM, Haiman CA, Hallmans G, Hankinson SE, Harris CC, Henriksson R, Holly EA, Hong YC, Hoover RN, Hsiung CA, Hu N, Hu W, Hunter DJ, Hutchinson A, Jenab M, Johansen C, Khaw KT, Kim HN, Kim YH, Kim YT, Klein AP, Klein R, Koh WP, Kolonel LN, Kooperberg C, Kraft P, Krogh V, Kurtz RC, LaCroix A, Lan Q, Landi MT, Marchand LL, Li D, Liang X, Liao LM, Lin D, Liu J, Lissowska J, Lu L, Magliocco AM, Malats N, Matsuo K, McNeill LH, McWilliams RR, Melin BS, Mirabello L, Moore L, Olson SH, Orlow I, Park JY, Patiño-Garcia A, Peplonska B, Peters U, Petersen GM, Pooler L, Prescott J, Prokunina-Olsson L, Purdue MP, Qiao YL, Rajaraman P, Real FX, Riboli E, Risch HA, Rodriguez-Santiago B, Ruder AM, Savage SA, Schumacher F, Schwartz AG, Schwartz KL, Seow A, Wendy Setiawan V, Severi G, Shen H, Sheng X, Shin MH, Shu XO, Silverman DT, Spitz MR, Stevens VL, Stolzenberg-Solomon R, Stram D, Tang ZZ, Taylor PR, Teras LR, Tobias GS, Van Den Berg D, Visvanathan K, Wacholder S, Wang JC, Wang Z, Wentzensen N, Wheeler W, White E, Wiencke JK, Wolpin BM, Wong MP, Wu C, Wu T, Wu X, Wu YL, Wunder JS, Xia L, Yang HP, Yang PC, Yu K, Zanetti KA, Zeleniuch-Jacquotte A, Zheng W, Zhou B, Ziegler RG, Perez-Jurado LA, Caporaso NE, Rothman N, Tucker M, Dean MC, Yeager M, Chanock SJ. Female chromosome X mosaicism is age-related and preferentially affects the inactivated X chromosome. Nat Commun. 2016;7:11843.
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This page was last updated on November 1st, 2017