Education and career
Baccarelli graduated cum laude with a medical degree from the University of Perugia,Italy in 1995,obtained his Master of Science in Epidemiology from the University of Turin,Italy,and his Ph.D. in Occupational Health and Industrial Hygiene from the Universita' degli Studi di Milano,Italy,in 2003. [3]
He completed his residency in endocrinology at the University of Milan and his postdoctoral fellowship at the National Cancer Institute's Division of Cancer Epidemiology and Genetics (2000–2004). [4]
Baccarelli has served as the Dean of the Faculty at the Harvard T.H. Chan School of Public Health since January 2024. He previously taught at the Harvard Chan School as the Mark and Catherine Winkler Associate Professor of Environmental Epigenetics from 2010 to 2016. [5]
He also served as Professor and Chair of the Department of Environmental Health Sciences at the Columbia University Mailman School of Public Health from 2016 to 2023. [6] [7] While at Columbia,he led the NIEHS Center for Environmental Health and Justice in Northern Manhattan,which brought together scientists,advocates,community organizations and the public to understand health concerns caused by environmental exposures and to address inequities. [8]
Baccarelli's research has pioneered the field of public health epigenetics,which explores how environmental factors can modify gene expression without changing the DNA sequence. [9] His studies have demonstrated that air pollution can alter the epigenome,leading to changes in gene regulation that may contribute to the development of diseases such as cardiovascular disorders and neurodegenerative conditions. [10] [11]
Baccarelli conducted research showing that short-term exposure to air pollution,including levels considered "acceptable," can impair cognitive ability in the elderly. [12] [13] [14] Baccarelli also found that the use of nonsteroidal anti-inflammatory drugs such as aspirin partially protected against the negative cognitive effects of pollution. [15] He also conducted research showing that ambient air pollution is associated with an increased risk of osteoporosis and bone fractures in older individuals. [16] [17]
In biology, epigenetics is the study of heritable traits, or a stable change of cell function, that happen without changes to the DNA sequence. The Greek prefix epi- in epigenetics implies features that are "on top of" or "in addition to" the traditional genetic mechanism of inheritance. Epigenetics usually involves a change that is not erased by cell division, and affects the regulation of gene expression. Such effects on cellular and physiological phenotypic traits may result from environmental factors, or be part of normal development. Epigenetic factors can also lead to cancer.
5-Methylcytosine is a methylated form of the DNA base cytosine (C) that regulates gene transcription and takes several other biological roles. When cytosine is methylated, the DNA maintains the same sequence, but the expression of methylated genes can be altered. 5-Methylcytosine is incorporated in the nucleoside 5-methylcytidine.
Environmental health is the branch of public health concerned with all aspects of the natural and built environment affecting human health. To effectively control factors that may affect health, the requirements that must be met to create a healthy environment must be determined. The major sub-disciplines of environmental health are environmental science, toxicology, environmental epidemiology, and environmental and occupational medicine.
Malignant transformation is the process by which cells acquire the properties of cancer. This may occur as a primary process in normal tissue, or secondarily as malignant degeneration of a previously existing benign tumor.
An environmental factor, ecological factor or eco factor is any factor, abiotic or biotic, that influences living organisms. Abiotic factors include ambient temperature, amount of sunlight, air, soil, water and pH of the water soil in which an organism lives. Biotic factors would include the availability of food organisms and the presence of biological specificity, competitors, predators, and parasites.
Air pollution is the contamination of air due to the presence of substances called pollutants in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. It is also the contamination of the indoor or outdoor environment either by chemical, physical, or biological agents that alters the natural features of the atmosphere. There are many different types of air pollutants, such as gases, particulates and biological molecules. Air pollution can cause diseases, allergies, and even death to humans; it can also cause harm to other living organisms such as animals and crops, and may damage the natural environment or built environment. Air pollution can be caused by both human activities and natural phenomena.
Transgenerational epigenetic inheritance is the proposed transmission of epigenetic markers and modifications from one generation to multiple subsequent generations without altering the primary structure of DNA. Thus, the regulation of genes via epigenetic mechanisms can be heritable; the amount of transcripts and proteins produced can be altered by inherited epigenetic changes. In order for epigenetic marks to be heritable, however, they must occur in the gametes in animals, but since plants lack a definitive germline and can propagate, epigenetic marks in any tissue can be heritable.
Cancer epigenetics is the study of epigenetic modifications to the DNA of cancer cells that do not involve a change in the nucleotide sequence, but instead involve a change in the way the genetic code is expressed. Epigenetic mechanisms are necessary to maintain normal sequences of tissue specific gene expression and are crucial for normal development. They may be just as important, if not even more important, than genetic mutations in a cell's transformation to cancer. The disturbance of epigenetic processes in cancers, can lead to a loss of expression of genes that occurs about 10 times more frequently by transcription silencing than by mutations. As Vogelstein et al. points out, in a colorectal cancer there are usually about 3 to 6 driver mutations and 33 to 66 hitchhiker or passenger mutations. However, in colon tumors compared to adjacent normal-appearing colonic mucosa, there are about 600 to 800 heavily methylated CpG islands in the promoters of genes in the tumors while these CpG islands are not methylated in the adjacent mucosa. Manipulation of epigenetic alterations holds great promise for cancer prevention, detection, and therapy. In different types of cancer, a variety of epigenetic mechanisms can be perturbed, such as the silencing of tumor suppressor genes and activation of oncogenes by altered CpG island methylation patterns, histone modifications, and dysregulation of DNA binding proteins. There are several medications which have epigenetic impact, that are now used in a number of these diseases.
Behavioral epigenetics is the field of study examining the role of epigenetics in shaping animal and human behavior. It seeks to explain how nurture shapes nature, where nature refers to biological heredity and nurture refers to virtually everything that occurs during the life-span. Behavioral epigenetics attempts to provide a framework for understanding how the expression of genes is influenced by experiences and the environment to produce individual differences in behaviour, cognition, personality, and mental health.
An epigenetic clock is a biochemical test that can be used to measure age. The test is based on DNA methylation levels, measuring the accumulation of methyl groups to one's DNA molecules.
Epigenetic therapy refers to the use of drugs or other interventions to modify gene expression patterns, potentially treating diseases by targeting epigenetic mechanisms such as DNA methylation and histone modifications.
Kari C. Nadeau is the Chair of the Department of Environmental Health at Harvard School of Public Health and John Rock Professor of Climate and Population Studies. She is also adjunct professor at Stanford University in the Department of Pediatrics. She practices Allergy, Asthma, Immunology in children and adults as a physician, and has published over 400 papers. Her team focuses on quantifying health outcomes of solutions as they pertain to air pollution mitigation and adaptation at the local, regional, country, and global levels. Dr. Nadeau, with a team of individuals and patients and families, has been able to help major progress and impact in the clinical fields of exposomics, immunology, infection, asthma, and allergy. Dr. Nadeau is a member of the National Academy of Medicine and the U.S. EPA Children’s Health Protection Committee.
An epigenome-wide association study (EWAS) is an examination of a genome-wide set of quantifiable epigenetic marks, such as DNA methylation, in different individuals to derive associations between epigenetic variation and a particular identifiable phenotype/trait. When patterns change such as DNA methylation at specific loci, discriminating the phenotypically affected cases from control individuals, this is considered an indication that epigenetic perturbation has taken place that is associated, causally or consequentially, with the phenotype.
Epigenetics of anxiety and stress–related disorders is the field studying the relationship between epigenetic modifications of genes and anxiety and stress-related disorders, including mental health disorders such as generalized anxiety disorder (GAD), post-traumatic stress disorder, obsessive-compulsive disorder (OCD), and more. These changes can lead to transgenerational stress inheritance.
Gene-environment interplay describes how genes and environments work together to produce a phenotype, or observable trait. Many human traits are influenced by gene-environment interplay. It is a key component in understanding how genes and the environment come together to impact human development. Examples of gene-environment interplay include gene-environment interaction and gene-environment correlation. Another type of gene-environment interplay is epigenetics, which is the study of how environmental factors can affect gene expression without altering DNA sequences.
Frederica Perera is an American environmental health scientist and the founder of the Columbia Center for Children's Environmental Health at the Columbia University Mailman School of Public Health. Her research career has focused on identifying and preventing harm to children from prenatal and early childhood exposure to environmental chemicals and pollutants. She is internationally recognized for pioneering the field of molecular epidemiology, incorporating molecular techniques into epidemiological studies to measure biologic doses, preclinical responses and susceptibility to toxic exposure.
Stephanie J. London is an American epidemiologist and physician-scientist specializing in environmental health, respiratory diseases, and genetic susceptibility. She is the deputy chief of the epidemiology branch at the National Institute of Environmental Health Sciences.
Environmental epigenetics is a branch of epigenetics that studies the influence of external environmental factors on the gene expression of a developing embryo. The way that genes are expressed may be passed down from parent to offspring through epigenetic modifications, although environmental influences do not alter the genome itself.
Nutritional epigenetics is a science that studies the effects of nutrition on gene expression and chromatin accessibility. It is a subcategory of nutritional genomics that focuses on the effects of bioactive food components on epigenetic events.
Epiphenotyping involves studying the relationship between DNA methylation patterns and phenotypic traits in individuals and populations to be able to predict a phenotype from a DNA methylation profile. In the following sections, the background of epiphenotyping, an overview of a general methodology, its applications, advantages, and limitations are covered.
