Guillaume Lettre, Ph.D.

Guillaume Lettre is a professor of medicine at the Université de Montréal and a principal investigator at the Montreal Heart Institute. He holds the Canada Research Chair in Complex Trait Genetics and is an elected member of the College of the Royal Society of Canada.

In December 2008, he completed 3.5 years of postdoctoral training in the lab of Joel N. Hirschhorn at the Broad Institute and Children’s Hospital Boston working on the genetics of complex human traits using genome-wide association studies. Guillaume obtained his BSc in Biology from the Université de Sherbrooke (2000) and his MSc in Biological Sciences from Cold Spring Harbor Laboratory (2001). In 2005, he completed his PhD in Developmental Genetics at the University of Zurich. Beside genetics, Guillaume likes running, ice hockey and old red Bordeaux.


Ken Sin Lo

Ken Sin Lo joined the group in March 2009 as lead bioinformatician. He oversees computational work in the lab, manages the big data and acts as webmaster.

Chao-Sheng Lo, Ph.D.

Chao-Sheng Lo joined Dr. Lettre’s lab in August 2023 as a research assistant. He works closely with bioinformaticians in his lab using a range of techniques including CRISPR knockout, inhibition activation, and base editing to understand the impact of single nucleotide polymorphisms on cardiovascular disease-associated genetic variants. He completed his post-doctoral training at the Centre de recherche de l’Hôpital de l’Université de Montréal (CRCHUM) and the Montreal Diabetes Research Center (MDRC). He has gained extensive experience in the field of hypertension and diabetes. He has elucidated the complex mechanisms of gene regulation under pathophysiological conditions using tissue-specific transgenic and knockout mouse models. He is passionate about discovering causative variants and mechanisms in the genetics of human disease.

Hicham Belhaj, M.Sc.

Hicham Belhaj joined Dr. Guillaume Lettre’s laboratory in November 2021 as a research assistant. He works jointly with members of the laboratory to identify, among thousands of genes, those involved in hypertension and endothelial dysfunction by CRISPR/Cas9 screen. Hicham obtained a bachelor’s and a master’s degree in molecular and cellular biology at the University of Montreal. During his master’s degree, he became interested in the molecular mechanisms of the last step in cell division, cytokinesis. In particular, he was interested in a protein known to be overexpressed in various cancers, anillin.


Rose Laflamme

Rose Laflamme started her master in bioinformatics in Dr Lettre’s lab in the fall semester of 2022. She obtained her bachelor in bioinformatics at the Université de Montréal in spring 2022. Rose discovered the lab and its team when she did a summer internship in 2021, working on transcriptomics changes caused by the aging of vascular endothelial cells. Her field of interest is genetics and genomics, hence her master project studying structural variants in a population cohort of Quebec.

Estelle Lecluze, Ph.D.

Estelle Lecluze joined Dr Guillaume Lettre’s lab in September 2020 as a post-doctoral fellow. She is working on the role of endothelial cells in blood pressure regulation. She identifies important genes that may be responsible of endothelial dysfunction by analyzing genomics, epigenomics and transcriptomics data, and participates to functional genomic experiments using CRISPR/Cas9 technology.

Francis Leblanc

Francis Leblanc joined Dr Guillaume Lettre’s lab in May 2018 for a summer internship on endothelial dysfunction. Francis returns to higher education after 10 years in the health and fitness industry. He completed the bachelor in biochemistry with honors at the University of Montreal in April 2019, and is now a PhD student in bioinformatics. His projects will integrate bulk and single nuclei RNAseq and ATACseq to further the molecular understanding of atrial fibrillation and endothelial dysfunction.

Pegah Hejazi, M.Sc.

Pegah Hejazi joined Dr. Lettre’s lab in January 2022 as a PhD student. She is working on single cell methods to study cardiovascular diseases. Precisely, she is interested in transcriptomic and epigenetic of cellular senescence in cardiovascular dysfunction.
Pegah has finished her Masters in Biotechnology. During that time she was involved in cancer research and drug discovery.

Thomas Pincez, M.D., M.Sc.

Thomas Pincez joined the group in January 2020 as a molecular biology PhD’s student. He is interested in red cell genetics and especially sickle cell disease. He will work from genome-wide association data and CRISPR-Cas9 screening.

After medical school and paediatrics residency in Paris, France, Thomas has started a fellowship in haematology-oncology paediatrics at Ste-Justine hospital, Montreal, until the end of 2020. He also has a master degree in immunology.

Nicolas Brosseau, M.Sc.

Nicolas Brosseau joined the group in june 2020 as a PhD student. He is working on the influence of genetique variations on red blood cells traits and the influence these variations have on the severity of sickle cell disease.

Nicolas obtained is BSc and MSc in biomedical sciences at the Université de Montréal. During his master, he studied the resistance mechanisms of cancer cells to chemotherapeutic treatments. More specifically, he was interested by the involvement of membrane transport in the uptake of anthracyclines by targeted cells.

Jennifer Zevounou

Jennifer Zevounou joined Dr. Guillaume Lettre’s laboratory in the fall of 2023 as a master’s student in Biomedical Sciences, after obtaining her bachelor’s degree in Life Sciences/Bioinformatics in June 2023 at the University of Paris Cité. She is interested in genetic variants affecting endothelial function and associated with the development of cardio- and cerebro-vascular diseases.

Vanessa Bellegarde

Vanessa Bellegarde joined Dr. Guillaume Lettre’s laboratory in May 2022 as a summer intern to study structural variants in a Quebec cohort. She obtained her bachelor’s degree in bioinformatics from the University of Montreal in the spring of 2023. She rejoined Dr. Lettre’s team in the fall of 2023 to pursue her master’s degree in bioinformatics, which focuses on transcriptomic analysis of hematopoietic stem cells in sickle cell anemia.

Arnaud Chignon, Ph.D.

Arnaud Chignon.



Stronger et al. 2013