• Associate Professor, School Of Biological Sciences


  • Johnson, C. M., & Phadnis, N. A cancer in hybrids. PNAS, Jan 19;118(3):e2023488118. doi: 10.1073/pnas.2023488118. Published, 01/2021.
  • Fuller,Z.L.,Koury,S.A.,Leonard,C.J.,Young,R.E.,Ikegami,K,Westlake,J.,Richards,S., Schaeffer, S.W., & Phadnis, N. Extensive recombination suppression and epistatic selection causes chromosome-wide differentiation of a selfish sex chromosome in Drosophila pseudoobscura. Genetics. 2020 Sep;216(1):205-226. Published, 09/2020.
  • Cooper JC, Lukacs A, Reich S, Schauer T, Imhof A & Phadnis N (2020). Altered Localization of Hybrid Incompatibility Proteins in Drosophila. Molecular biology and evolution. Vol. 36, 1783-1792. Published, 02/01/2020.
  • King TD, Leonard CJ, Cooper JC, Nguyen S, Joyce EF & Phadnis N (2020). Recurrent Losses and Rapid Evolution of the Condensin II Complex in Insects. Molecular biology and evolution. Vol. 36, 2195-2204. Published, 01/01/2020.
  • Fuller ZL, Koury SA, Phadnis N & Schaeffer SW (2019). How chromosomal rearrangements shape adaptation and speciation: Case studies in Drosophila pseudoobscura and its sibling species Drosophila persimilis. Molecular ecology. Vol. 28, 1283-1301. Published, 11/01/2019.
  • Cooper, J.C. & Leonard,C.J.,Pederson,B.,Carey,C.,Quinlan,A.,Elde,N.C.,&Phadnis,N. (2019). Endless conflicts: Detecting molecular arms races in mammalian genomes. bioRxiv 685321. Published, 06/28/2019.
  • Cooper, J.C. & Guo, P., Bladen, J., & Phadnis, N (2019). A triple-hybrid cross reveals a new hybrid incompatibility locus between D. melanogaster and D. sechellia. bioRxiv 590588. Published, 04/04/2019.
  • Fuller, Z.L. & Koury,S.A.,Leonard,C.J.,Young,R.E.,Ikegami,K,Westlake,J.,Richards,S., Schaeffer, S.W., & Phadnis, N (2018). Extensive recombination suppression and chromosome-wide differentiation of a segregation distorter in Drosophila. bioRxiv 504126. Published, 12/21/2018.
  • J.C. Cooper & Nitin Phadnis (2017). Parallel evolution of sperm hyper-activation Ca2+ channels. Genome Biology and Evolution. Vol. 9, 1938-1949. Published, 07/11/2017.
  • Nitin Phadnis (2017). Poisons, antidotes and selfish genes. Science. Vol. 356, 1013. Published, 06/09/2017.
  • Cooper, J.C. & Phadnis, N. (2016) A genomic approach to identify hybrid incompatibility genes. Fly, 10(3):142-8.. Published, 07/02/2016.
  • Phadnis, N., Baker, E.P., Cooper, J.C., Frizzell, K., Hseih, E., de la Cruz, A.F., Shendure, J, Kitzman, J., and Malik, H.S. An essential cell cycle regulation gene causes hybrid inviability in Drosophila. Science, 350: 1552-1555. Published, 12/2015.
  • Lee, J.E., Oney, M., Frizzell, K., Phadnis, N., and Hollien, J. Drosophila melanogaster activating transcription factor 4 regulates glycolysis during endoplasmic reticulum stress. G3 (Bethesda). 13;5(4):667-75. Published, 02/2015.

Research Statement

Speciation – the process by which one species splits into two – involves the evolution of reproductive isolating barriers such as the sterility or inviability of hybrids between populations. Even in his seminal masterpiece “On The Origin of Species”, Darwin could find no satisfactory solution to the apparent paradox of why natural selection would tolerate the evolution of severely detrimental traits such as sterility and inviability and, therefore, termed this problem the "mystery of mysteries". This “mystery of mysteries” is one of the most important and unanswered questions in biological research over the past 150 years: how do two species evolve from one? 

The Phadnis Lab takes a multi-disciplinary approach that leverages the power of genetics, genomics and cell biology to understand the molecular basis of speciation in Drosophila. In particular, we would like to understand broad patterns of the molecular pathways which, when tinkered by evolution, become incompatible between species and lead to the sterility or inviability of hybrids. The Phadnis Lab uses a combination of classical genetics and genomics approaches to identify genes that cause hybrid sterility or inviability, and cell biological approaches to understand the molecular basis of hybrid dysfunction. We are also interested in investigating the role of intra-genomic conflict involving segregation distorters as a driving force in speciation and in understanding the molecular mechanisms used by these selfish elements to tip the balance of meiosis in their own favor.

Research Keywords

  • Speciation
  • Selfish genetic elements
  • Molecular Evolution


  • Pew Meeting, online. Contributed Talk, Presented, 09/2021.
  • Annual Drosophila Research Conference, online. Invited Talk/Keynote, Presented, 06/2021.
  • Quantitative and Systems Biology, University of California, Merced. Invited Talk/Keynote, Presented, 10/2019.
  • Integrative Biology, University of California, Berkeley. Invited Talk/Keynote, Presented, 09/2019.
  • Department of Biology, University of Oregon. Invited Talk/Keynote, Presented, 09/2019.
  • University of North Carolina, NC. Invited Talk/Keynote, Presented, 08/2019.
  • Biological Sciences, UMass Amherst, MA. Invited Talk/Keynote, Presented, 08/2019.
  • Systems Biology, Harvard Medical School, MA. Invited Talk/Keynote, Presented, 08/2019.
  • Drosophila Heterochromatin Meeting, Spoleto, Italy. Contributed Talk, Presented, 06/2019.
  • Harvard University, OEB, MA. Invited Talk/Keynote, Presented, 10/2018.
  • Duke University, Department of Biology, NC. Invited Talk/Keynote, Presented, 10/2018.
  • Utah State University, UT. Invited Talk/Keynote, Presented, 09/2018.
  • Laurentian University, ON, Canada. Invited Talk/Keynote, Presented, 09/2018.
  • Memorial Sloan Kettering Institute, NY. Invited Talk/Keynote, Presented, 09/2018.
  • Biology of Genomes, Cold Spring Harbor Laboratories. Invited Talk/Keynote, Presented, 10/2017.
  • University of Montana, Missoula, MT. Invited Talk/Keynote, Presented, 07/13/2017.
  • Drosophila Heterochromatin Meeting, Cagliari, Italy. Contributed Talk, Presented, 06/08/2017.
  • Plenary speaker: Annual Drosophila Research Conference, San Diego. Invited Talk/Keynote, Presented, 03/31/2017.
  • Pew Scholars Meeting, Santa Barbara, CA. Invited Talk/Keynote, Presented, 03/07/2017.
  • Keynote speaker, Developmental Biology Retreat, Northwestern University. Invited Talk/Keynote, Presented, 10/20/2016.