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Human Genetics Branch Human Genetics Branch


Photo of Francis McMahon

Francis J. McMahon, M.D., Principal Investigator

Dr. McMahon received a B.A. in Biology from the University of Pennsylvania in 1982 and an M.D. from Johns Hopkins in 1987, where he also completed a medical internship, a residency in adult psychiatry, and a post-doctoral fellowship in genetics. In 1998, he moved to the University of Chicago, where he continued his research into the genetics of bipolar disorder while serving as Medical Director of the electroconvulsive therapy clinic. In 2002, he joined the Mood and Anxiety Disorders Program of the National Institute of Mental Health (NIMH) Intramural Research Program as Chief of its genetics unit. In 2010, he was promoted to Senior Investigator and Chief of the Human Genetics Branch. He is also a visiting Professor of Psychiatry at the Johns Hopkins University School of Medicine.

Dr. McMahon’s research is aimed at discovering and characterizing genes involved in mood and anxiety disorders so that better methods of diagnosis and treatment can be developed.

Dr. McMahon is past President of the International Society of Psychiatric Genetics and a Fellow in the American College of Neuropsychopharmacology. He serves on the editorial boards of Biological Psychiatry, International Review of Psychiatry, and Molecular Neuropsychiatry, and is a scientific advisor for the American Society for the Prevention of Suicide and the Rutgers University Cell & DNA Repository. He has received several awards for his work, including the 2016 Colvin Mood Disorders Prize from the Brain & Behavior Research Foundation. He has authored over 200 scientific reports and textbook chapters.

Ian Adoremos, B.A., Postbaccalaureate Fellow

Ian graduated with a B.A. in Cognitive Science from University of Virginia. His research focus is on developing quantitative tools for analyzing and integrating next-generation sequencing data sources that come from individuals with bipolar disorder. He plans to pursue a Ph.D. in Neuroscience after his tenure at the NIH. In his free time, he enjoys listening to Classical Music, meditating, painting and reading German philosophy.

Nirmala Akula, M.S., Ph.D., Bioinformaticist

Dr. Akula received a master's in biotechnology from India in 1997. She then came to USA and earned a master's in biology from Illinois Institute of Technology in 2001 and a master's in computer science from University of Chicago in 2002. She graduated with a Ph.D. in bioinformatics from George Mason University in January, 2010. She has been working on the genetics of major mood disorders since 2000. She conducts genome-wide association studies (GWAS) and analyzes next-generation sequencing data. She recently developed a software tool, Network Interface Miner for Multigenic Interactions (NIMMI) that identifies susceptible networks/ pathways using GWAS data.

Ifeoma Akwue, B.S., Postbaccalaureate Fellow

Ifeoma graduated with a B.S. in Psychology from the University of Florida with an emphasis in Behavioral and Cognitive Neuroscience. She joined the clinical team in June 2023. After leaving the NIH, Ifeoma plans to pursue her Ph.D. in Clinical Psychology.

Emily K. Besançon, LICSW, LPC, Clinical Research Coordinator

Emily K. Besançon earned a master's degree in Social Work from the University of Michigan. Prior to working with the Human Genetics team, she worked clinically in the District of Columbia with youth and families who have mood and behavioral diagnoses. Here, she also worked as a family therapist and then as a supervisor of a team which addressed youth with sexual offending behaviors. She began her career working with previously homeless adults, many of whom had co-occurring diagnoses. A significant amount of her experience has included working cross-culturally including with British, Australian, and asylum seeking populations. Additionally, Emily has worked in private practice and with youth involved in the foster care system.

Claudia C.V. da Silva-Camargo, M.S., Ph.D., Visiting Fellow

Dr. da Silva-Camargo received her degree in Pharmacy/Biochemistry, graduate degree in Human Genetic and Genomic, Master and Ph.D. in Health Sciences from the Pontifical Catholic University of Paraná in Brazil. She did her Ph.D. in collaboration with Georgetown University, Washington-DC, USA. Her prior research interests focus on oncogenetics and neurogenetics. She develops projects involving genetic risk factors for autism spectrum disorder and tumor development, applying techniques of immunohistochemistry, cell culture and molecular biology. She started her activities at NIMH/NIH in June 2023 as a Visiting Post Doctoral, her research focus is Genetic and Biology of Neuropsychiatric diseases.

Theresa B. DeGuzman, B.S., Program Specialist

Ms. DeGuzman is primarily involved in managing the lab’s sample inventory and administering the receiving database. She also assists with regulation compliance as well as graphic design and artwork. She has been with the NIMH Intramural Program since 1998 where she previously worked as a research assistant for the Laboratory of Clinical Science. She prepared clinical data on OCD and other comorbid disorders for analysis and did some of the preliminary statistical analysis. She designed, structured and administered her previous lab’s main clinical sample database and mouse database. She received her B.S. in Psychology degree from Letran College, Manila, Philippines.

Gabi Dugan, B.S., Postbaccalaureate Fellow

Gabi received her B.S. from Virginia Tech in biological systems engineering. She is passionate about studying the genetic architecture of neuropsychiatric disorders and joined the NIMH Intramural Program in July 2022. After her time at the NIMH, she hopes to pursue a Ph.D. in bioinformatics and neuroscience.

Sevilla Detera-Wadleigh, Ph.D., Staff Scientist

Dr. Detera-Wadleigh's (M.S., Ph.D. Biochemistry) research has focused on the genetics of mood disorders. To identify potential susceptibility regions for bipolar disorder she performed genome-wide linkage scan in multiply affected pedigrees, initiated and assembled the first large genome scan meta-analysis, involving many investigators in multiple countries. She has been involved in genome-wide association studies for bipolar disorder. She cloned neurobiologically relevant genes including rat MAPK (ERK1), human CALM 2 and human glucocorticoid receptor gene and characterized its promoter. She also cloned IMPA2, which encodes myoinositol monophosphatase, an enzyme known to be inhibited by lithium. In line with her interest in systems genetics of bipolar disorder, recently she generated molecular interaction networks which revealed enriched pathways for lithium-responsive genes and bipolar disorder candidate genes. She is pursuing studies on cellular modeling of bipolar disorder through induced pluripotent stem cells and is involved in a collaborative effort with the Institute for Systems Biology to perform whole genome sequencing in multigenerational multiply affected bipolar pedigrees to identify disease-segregating variants.

Ally Freifeld, B.A., Postbaccalaureate Fellow

Ally joined the Clinical Team of the GBMAD Lab in July 2022, after graduating with a B.A. in Psychology and minors in Education and Spanish from Duke University. After her time at the NIMH, Ally hopes to pursue an education in Clinical Psychology and eventually work as a clinician with children and adolescents.

Girma W. Hawariat, Ph.D., Statistician and Quantitative Geneticist

Dr. Hawariat received his B.S. in Biology from Haile Sellassie University, Ethiopia and M.S. and Ph.D. degrees in quantitative genetics from Texas A&M University. He did his postdoctoral training in quantitative genetics at The University of Wisconsin-Madison and a second postdoctoral training in molecular/cellular biology in The College of Medicine of The State University of New York at Syracuse. He served as a research scientist in molecular/cellular biology of cancer at The George Washington University Medical Center (Children Hospital) and as an assistant Professor in the same area in The College of Medicine of The Uniformed Services University of The Health Sciences. Dr. Hawariat has authored and co-authored 16 papers.

Xueying Jiang, M.D., Ph.D., Biologist

Dr. Jiang received her M.D. from XinJiang Medical School in China in 1988, and her Ph.D. in pharmacology at Chinese Academy of Medical sciences & Peking Union Medical College Peking in 1994. She completed her postdoctoral training at Department of Pharmacology, University of Maryland. From 2001 to 2006, she worked as a research assistant professor in the Department of Neurology, Uniformed Services University of the Health Sciences (USUHS), and participated in several research projects conducted by both National Institute on Alcohol Abuse and Alcoholism (NIAAA) and USUHS. Then she worked as a research scientist at the NIAAA/NIH, Section of Molecular Neurogenetics in the Laboratory of Neurogenetics for 2 years. She joined our group at the end of 2008.

Layla Kassem, Ph.D., Psy.D., Psychologist

Dr. Kassem completed her doctorate in clinical psychology in 1993. She completed her postdoctoral training in Boston and Chicago. She is currently working on two projects. The first is at NIMH/NIH, at the Genetics of Mood and Anxiety Disorders Section, and the second is at the University of Chicago in the Committee on Human Development. Her interests include genetics of chronic psychiatric disorders and cultural issues in diagnosis and treatment. Her main responsibilities at NIMH include family interviews, and the analysis of clinical data. Her work at University of Chicago includes cross-cultural research on psychiatric disorders and their phenotypes as well as the interface between traditional healers and trained psychotherapists, and the evolution of the field of psychiatry in Lebanon and Egypt.

Ley Nadine Lacbawan, M.D., M.B.A., M.P.H., Postdoctoral Fellow

Dr. Lacbawan received her Doctor of Medicine and Master of Business Administration from the Ateneo de Manila University School of Medicine and Public Health and has a Master of Public Health in Global Health from The George Washington University. She has more than six years of clinical and laboratory research experience in clinical, biochemical, and molecular genetics, neurology, and psychology resulting in a book chapter, various publications, and presentations at scientific meetings. As a postdoctoral fellow, she works both in the laboratory and with the clinical study team. She is studying how different medications used to treat mental illnesses like bipolar disorder affect neurons at the molecular level. She also conducts thorough interviews and processes some of the blood samples from our study volunteers.

Marlene Lawston, Oxcam/NIH Graduate Student

Marlene received her B.A. in Molecular Biology and Chinese from Colgate University in 2020. During her time at Colgate, Marlene completed an honors thesis investigating sensory organ development and regeneration in blind cavefish (Astyanax mexicanus) – this project provided the basis for her successful Beckman and Goldwater Scholarships. After graduating from Colgate, Marlene began her M.D./Ph.D. studies at the University of Rochester School of Medicine and Dentistry. While she always had an interest in molecular neurobiology from her prior studies, learning neuroscience and genetics during her first two years in medical school solidified neuro-genetics as a primary interest both clinically and from a research perspective. Marlene is an NIH-Oxford Scholar currently working towards a D.Phil. in Biomedical Sciences under the supervision of Dr. Francis McMahon (NIMH) and Professor Francis Szele (Oxford). She is using human iPSC and organoid models to better understand the genetics and cell types underlying developmental and neuropsychiatric disorders.

Anton Schulmann, M.D., Research Fellow

Dr. Schulmann earned his medical degree from Heidelberg University, Germany, where his doctoral thesis focused on molecular neurobiology of glutamatergic synapses. In his postdoctoral training at UC Irvine and HHMI’s Janelia Research Campus, he gained expertise in functional genomics in both rodent and human brain tissue. In his current role at the NIMH, Dr. Schulmann collaborates closely with the Human Brain Collection Core and uses single-cell genomics and spatial transcriptomics to better understand how known genetic risk variants impact the human brain and predispose to psychiatric disease. Dr. Schulmann recently received a K22 award to support his ongoing work on cell types in the mediodorsal thalamus and their role in schizophrenia and bipolar disorder.

Rachel Smith, OxCam/NIH Graduate Student

Rachel Smith is a Ph.D. candidate in Psychiatry (expected spring 2025) supervised by Dr. Francis McMahon and Armin Raznahan at NIMH HGB and Professors Ed Bullmore and Petra Vértes at the University of Cambridge Department of Psychiatry Brain Mapping Unit. Her work focuses on the neurodevelopmental impact of early life stress and its links to adulthood neuropsychiatric disorders. She uses a variety of computational techniques, from network neuroscience and bioinformatics, in both humans and rats, to explore this question. Previously, Rachel graduated in 2019 from the College of William and Mary with a BS in Neuroscience and minor in Arabic Language and Literature. She completed her post-baccalaureate fellowship in the vascular physiology lab of Dr. Hans Ackerman at NIAID, using wet and dry lab approaches to study vascular disruptions in a variety of disease contexts, including Babesia rossi infection, cerebral malaria, and COVID-19. She matriculated in the NIH-Oxford-Cambridge Scholars Program in August 2021.

Heejong Sung, Ph.D., Statistical Geneticist

Dr. Sung received a master in (Applied) Mathematics from Ewha Womans University, South Korea in 2001. Then she earned her Ph.D. in Statistics from Stony Brook University, New York in 2006. She worked as a statistical geneticist at Computational and Statistical Genetics Branch at NHGRI until she joined NIMH in 2020. Her research focuses on the identification of genetic markers contributing to heritable human trait variation/diseases and the development of statistical methods for tests of association in genetic data on unrelated and related individuals.

Bala Susarla, Ph.D., Biologist, Gene Editing Specialist

Dr. Susarla earned her Ph.D. in Biochemistry from Osmania University in India. She completed her postdoctoral research at the University of Pennsylvania, where her work focused on protein kinase-C-dependent trafficking of glutamate transporters to and from the cell surface. She also sub-cloned FLAG-tagged EAAT1 into lentiviral vectors, which was expressed in rat astrocytes. Bala worked in the Pharmacology Department of the Uniformed Services University of Health Sciences, where she studied TGF-β mediated induction of chondroitin-sulfate proteoglycans using lentiviral shRNA for Smad2/3 proteins in primary astrocyte cultures. Most recently, at the Transgenic core of NIMH she designed transgenic DNA constructs using NEBuilder and applied CRISPR-Cas9 genome editing technology to generate transgenic animals. She joined Human Genetic Branch in November 2022 and will start employing CRISPR-Cas9 technology to determine the biological effects of knocking down genes that are significantly associated with human neuropsychiatric disorders.


Kwangmi Ahn, Ph.D., M.B.A.

Alejandro Arbona-Lampaya, B.S., Postbaccalaureate Fellow

Meghan C.C. Blattner, M.A., Clinical Researcher

Stephanie A. Cardenas, B.A., Postbaccalaureate Fellow

David Chen, M.D., Clinical Research Fellow

Winston R. Corona, M.S., Biologist

Joanna Cross, Ph.D., Research Fellow

Kenan Courtney, B.S., Postbaccalaureate Fellow

Alex D’Amico, B.S., Postbaccalaureate Fellow

Bryce England, B.S., B.A., Postbaccalaureate Fellow

Francis Gordovez, M.D-Ph.D. Candidate, Special Volunteer

Josh Garcia, Postbaccalaureate Fellow

Katie Hosey, Postbaccalaureate Fellow

Liping Hou, Ph.D., Visiting Fellow

Gonzalo Laje, M.D., M.Sc., Associate Clinical Investigator

Fabiana L Lopes, M.D., Ph.D., Research Fellow

Maame Mensah, Postbaccalaureate IRTA Fellow, Research Assistant

Eleanor Murphy, Ph.D., Research Fellow

Katie Posey, Postbaccalaureate IRTA Fellow, Research Assistant

Jill Russ, M.S., Biologist

Thomas Schulze, M.D., Professor of Psychiatric Genetics, University of Goettingen, Germany

Laura Sheridan, Postbaccalaureate IRTA Fellow, Research Assistant

Christopher Song, B.A., Postbaccalaureate IRTA Fellow, Research Assistant

Jens R. Wendland, M.D., Group Leader, Roche Pharmaceuticals, Bern, Switzerland

Lexie Wille, B.S., Postbaccalaureate IRTA Fellow, Research Assistant

Kevin Zhu, B.S., Postbaccalaureate IRTA Fellow, Research Assistant