We work to cultivate the next generation of X-linked Dystonia-Parkinsonism (XDP) research leaders with undergraduate research education, postdoctoral research fellowships and clinical research fellowships.

Postdoctoral Fellows

Dr. Domingo in the lab

Aloysius Domingo, PhD

Aloysius Domingo, MD, PhD is a postdoctoral fellow with Dr. Michael Talkowski, Chair of Genomic Medicine at MGH and Dr. Cristopher Bragg, Director of CCXDP with a research focus on the molecular genetic mechanisms surrounding primary dystonia in general, and in particular, of X-linked dystonia-parkinsonism. 

Dr. Domingo obtained his medical degree from the University of the Philippines College of Medicine and his training in Clinical Neurology at the Philippine General Hospital. He then pursued PhD studies in Molecular Life Sciences at the University of Lübeck, Germany.

Publications by Dr. Domingo

Katia E. Maalouf, PhD

Dr. Maalouf

Dr. Katia E. Maalouf is a postdoctoral fellow in Dr. Xandra Breakefield’s laboratory at Mass General and Harvard Medical School. She is currently studying the role of extracellular vesicles (EVs) in XDP. Dr. Maalouf obtained a PhD in Molecular Biochemistry from the Leibniz University of Hanover (LUH), Germany with emphasis in neurodegenerative diseases. She later joined the laboratory of Dr. Rose-Mary Boustany at the American University of Beirut (AUB) as a postdoctoral fellow. There she worked on testing the effect of various drugs on neurobehavioral and biochemical parameters in a mouse model of Batten’s disease.

Tiziana Petrozziello, PhD

Dr. Tiziana Petrozziello is a post-doctoral fellow in the laboratory of Ghazaleh Sadri-Vakili, MS, PhD at Mass General. Her research focuses on unveiling the molecular mechanisms underlying neurodegeneration and neuroinflammation in neurodegenerative diseases, including XDP.

Dr. Petrozziello

Dr. Petrozziello obtained her PhD in Neuroscience at the University of Naples “Federico II” (Naples, Italy) focusing on a novel neuromodulatory role of SOD1 in amyotrophic lateral sclerosis. Following completion of her PhD she began a post-doctoral fellowship in Dr. Annunziato’s laboratory in the Department of Neuroscience at University of Naples “Federico II,” where her studies focused on ionic homeostasis imbalance in ALS.

In 2019, she joined Dr. Sadri-Vakili’s laboratory and began her studies on XDP. Her efforts are focused on determining the role of neuroinflammation XDP pathogenesis and identifying new therapeutic targets for the treatment of XDP using human post-mortem brains, as well as fibroblasts derived from patients. Thus far, Dr. Petrozziello’s findings have unveiled an epigenetic target as well as key immune markers involved in inflammation that lay the groundwork for the development of therapies for XDP.

Publications by Dr. Petrozziello

Alan Mejia-Maza, PhD

Alan Mejia-Maza, PhD
Dr. Mejia-Maza

Dr. Alan Mejia-Maza is a postdoctoral fellow in Dr. Vanessa Wheeler´s laboratory at Massachusetts General Hospital and Harvard Medical School. His research focuses on understanding the instability of the XDP hexameric repeat. Specifically, Dr. Mejia-Maza uses a range of genetic, molecular and bioinformatic analyses in patient samples and in patient-derived induced pluripotent stem cell (iPSC) and neuronal models to identify factors that modify hexameric repeat instability in XDP.

Dr. Mejia-Maza obtained his PhD in Neuroscience from the Queen Square Institute of Neurology, University College London (UCL) under the supervision of Prof. Elizabeth Fisher. His work at UCL focused on mouse models of Amyotrophic Lateral Sclerosis with special emphasis on neuromuscular junctions.

Charles Jourdan F. Reyes, PhD 

Dr. Reyes

Charles Jourdan F. Reyes, PhD is a postdoctoral research fellow in the laboratories of Prof. Clotilde Lagier-Tourenne and Prof. Cristopher Bragg at the Department of Neurology, Massachusetts General Hospital, and Harvard Medical School. He is currently investigating pathogenic mechanisms causing neuronal death in XDP and related neurodegenerative diseases. Charles graduated with a BS in Biology, Minor in History from the Ateneo de Manila University, Philippines. Then, with the support of a research scholarship from the Japanese Ministry of Education, Culture, Sports, Science, and Technology (MEXT), he finished his Master of Medical Science, focusing on RNA Biology and Neuroscience, at Osaka University Medical School. He recently obtained his PhD in Biomedicine, specializing in neurogenetics, at the University of Lübeck in Northern Germany through a German Catholic Academic Exchange (KAAD) scholarship.

Jamal Al Ali, MD

Dr. Al Ali

Dr. Al Ali completed a fellowship in the laboratory of Xandra O. Breakefield, PhD. As part of a collaboration with Dr. Nutan Sharma, Dr. Ali identified neurofilament light chain and TAF1 transcripts as XDP biomarkers. This work was published in Movement Disorders in 2021. Jamal is currently a Neurology resident at the University of Chicago.

Rachita Yadav, PhD

Dr. Yadav completed a postdoctoral fellowship with Dr. Laurie Ozelius in Neurology and Dr. Michael Talkowski in the Center for Genome Medicine (CGM). As a postdoc, she led part of the study which narrowed down the XDP associated region as defined by recombinations and discovered the role of SVA as the genetic cause of XDP by integrating genome and transcriptome sequencing using short-read and long-read technologies (Aneichyk*, Yadav*, et al., 2018, Cell, Bragg et al., 2018, PNAS).

Dr. Yadav

In 2021, Dr. Yadav was promoted to Instructor in Neurology at MGH and her current research focus is the integration of multi-dimensional genomics datasets associated with the genetic etiology of neurological disorders. The pathogenesis of neurological disorders often involves multiple genes, complex interactions thus, the functional genomics aspect of my project employs genome-wide and targeted transcriptomics analysis of neural cell lines and post-mortem brains from different neurological disorders to investigate common pathological mechanisms which concur among these disorders. Prior to joining MGH, Dr. Yadav trained in bioinformatics in India and earned a PhD at Denmark Technical University focusing on understanding the effect of genetic, epigenetic and clinical variations on the molecular mechanisms in complex phenotypes.

Publications by Dr. Yadav

Ranee Zara B. Monsanto, MD

Ranee Zara B. Monsanto, MD, is a research fellow in Dr. Ghazaleh Sadri-Vakili and Dr. Cristopher Bragg’s laboratories in the Department of Neurology at Massachusetts General Hospital and Harvard Medical School. Her research primarily focuses on investigating the role of neuroinflammation in the pathogenesis of X-linked Dystonia Parkinsonism.

Dr. Monsanto

Dr. Monsanto obtained her Bachelor of Science degree in Microbiology from the University of Santo Tomas and Doctor of Medicine from Far Eastern University - Dr. Nicanor Reyes Medical Foundation in the Philippines. She completed her medical internship training at the Philippine General Hospital before passing the Philippine Physician Licensure examination in 2016. She also finished her research internship in interdisciplinary neuroscience at Academia Sinica through the Taiwan International Graduate Program - International Internship Program (TIGP-IIP). Currently, Dr. Monsanto is a Master of Science in Molecular Medicine student at the St. Luke’s Medical Center - College of Medicine.


Clinical Fellows 

Melanie Supnet, MD

Dr. Supnet in the lab

Melanie Supnet, MD received an undergraduate degree in Pharmacy from University of Santo Tomas and Doctor of Medicine from same institution. She finished Neurology and Psychiatry training at University of Santo Tomas Hospital.

Dr. Supnet is currently a clinical research fellow under the direction of Dr. Nutan Sharma in the Movement Disorders Unit at MGH. Dr. Supnet conducts rigorous clinical measurements that include neurological, psychological and specialized assessments of people with many forms of dystonia. In addition to her research efforts, she has gained clinical exposure to the wide spectrum of movement disorders from the different types of dystonia, Parkinson’s disease, Spinocerebellar ataxia, Huntington’s disease, and functional disorders. At the end of her fellowship, the Dr. Supnet will have an expanded her expertise in understanding of the pathogenesis and proper management of these types of movement disorders. 

Publications by Dr. Supnet

Jan Kristoper P. de Guzman, MD

Dr. de Guzman in the lab

Jan Kristoper P. de Guzman, MD, earned his Bachelor of Science degree in Biology, cum laude, from the University of Santo Tomas in Manila, Philippines in 2007 and finished Doctor of Medicine in the same institution in 2011. He did his medical internship program at the University of Santo Tomas Hospital in Manila in 2012 and passed the Philippine Physician Licensure board examinations. He completed residency training in Neurology as associate chief resident at Jose R. Reyes Memorial Medical Center in Manila in 2015. 

Dr. de Guzman trained as a Research Fellow in Neurology’s Movement Disorders Unit at Massachusetts General Hospital under Dr. Nutan Sharma.  Here, he contributed to the research activities of the Collaborative Center for X-Linked Dystonia-Parkinsonism (CCXDP) as a research coordinator for the Dystonia Partners Research Bank and as an investigator for one project on co-morbidities of cervical dystonia and another project pinpointing the speech and swallow impairments of people with X-linked dystonia parkinsonism (XDP).  As a research coordinator and investigator, he conducted rigorous clinical measurements that include neurological, psychological and specialized speech and swallow assessments of people with many forms of dystonia.

Dr. de Guzman conducting clinical research in Panay

Dr. de Guzman returned to Manila in 2017 where he continues to pursue his interest in swallowing and speech impairments among patients with X-linked dystonia parkinsonism  Because fully understanding the unique phenomenology of this rare, neurodegenerative illness is essential to the identification of treatment targets and outcomes, he will also be involved in a major effort to study the natural history of XDP.

Publications by Dr. de Guzman

Christopher D. Stephen, MD, MRCP (UK), MSc

Dr. Stephen

Dr. Stephen is a board-certified attending neurologist at Massachusetts General Hospital (MGH) and Brigham & Women’s Hospital and an Instructor in Neurology at Harvard Medical School. Dr. Stephen treats patients with Parkinson's disease, tremor and other movement disorders, with a special interest in dystonia and ataxia.

From 2014-2016, Dr. Stephen trained as a Movement Disorders Fellow with Dr. Nutan Sharma at MGH. He now serves as a clinical investigator in an ongoing natural history study of XDP. His current research involves quantitative motor assessment of patients to better study the clinical course of XDP and other degenerative movement disorders.

Dr. Stephen obtained his medical degree at the University of Aberdeen in Scotland, UK and completed internal medicine residency training in the UK at the University of Edinburgh and University of Nottingham programs. After attaining his Membership of the Royal College of Physicians in 2009, he pursued further training as a specialist registrar in neurology at the University of Cambridge and was an Honorary Specialist Registrar at the National Hospital for Neurology and Neurosurgery, Queen Square, London, UK. He completed his internship and Neurology residency at the Beth-Israel Deaconess Medical Center/Children’s Hospital Harvard neurology program followed by a Fellowship in Movement Disorders and Ataxia at the combined Partners Mass General Brigham Massachusetts General Hospital and Brigham and Women's Hospital program with additional pediatric experience at Boston Children’s Hospital.

Undergraduate Students

Connie Cai
As a Harvard undergraduate, Connie Cai completed her senior thesis under the mentorship of Dr. Cristopher Bragg. Ms. Cai will attend Johns Hopkins Medical School after spending a year teaching in Taiwan as part of a Fulbright Scholarship.
Anne Cheng
Anne Cheng (Harvard class of 2017) was a thesis student in the Bragg Lab, where she researched the role of the SVA retrotransposon insertion within the TAF1 gene in XDP. After graduating with Honors in Neurobiology, she continued to work as a research assistant for the Wyss Institute’s MICrONS Brain Mapping Consortium within the Church Lab. She is now a medical student at Creighton University.
Christina Young Liu, MD
Dr. Liu spent multiple years conducting research as a Harvard undergraduate student in the Bragg lab. She is a co-author on first two publications for CCXDP, including the first stem cell model developed for XDP. After graduating, she earned her medical degree at Harvard and is now an orthopedics resident at Mass General.

David Shin
David Shin starting working on XDP as a Harvard undergraduate and after graduation worked as a technician for CCXDP for three years. He is a co-author on many of publications, including co-first author on an important paper in Cell, reporting the genetic cause of XDP. He accompanied the Mass General team to the Philippines where he presented his research. He is now a PhD student at the University of California, San Francisco.

Liam Power
Liam Power was a student in the Bragg lab for most of his undergraduate time at Harvard. He developed the screening assay that was used by our pharma partner to find candidate therapeutics for XDP. CCXDP is actively pursuing leads that came out of this screen and think a drug candidate could be ready for human testing in 2-3 years. He is now an MD PhD student at Tufts University.