Gene Expression


Human Genome

Modes of Inheritance

Genetic Mechanisms

Genetic Disease

Genetic Counseling

Gene Therapy

Mitochondrial Genetics

Population Genetics

Clinical Implications of Copy Number Variation in the Human Genome

Transmission of Genetic Disease



Knowledge derived from genomic discoveries is reshaping the underpinnings of much of medical practice. At a practical level, recent advances have taught us a tremendous amount about the basis of common conditions such as diabetes, heart disease, and cancer. This new knowledge is being rapidly translated into approaches for disease risk assessment, prevention, and treatment. Likewise, the study of how genes affect drug metabolism (pharmacogenetics) is being increasingly used to inform drug prescribing. 1

The study of how mutations in single genes cause rare disease (genetics) is gradually being eclipsed by research on how mutations in multiple genes interact with each other and the environment to result in health and disease (genomics).

The field of pathology has evolved to recognize that disease manifests in many cases as a direct reflection of changes in patterns of gene expression. There is also the recognition that gene expression patterns in a given lesion type (e.g., a certain form of cancer) will influence the clinical behavior of that lesion and its response to therapy. Hence, a great effort has been expended to characterize the genetic basis of various human diseases (molecular pathology), leading to a greater understanding of the contributions of genomic alterations to the development and progression of disease.


Using these techniques, genes influencing risk for many neuropsychiatric diseases have been identified. Solid evidence now supports specific common variants for schizophrenia and bipolar disorder, and specific rare variants for autism, schizophrenia and intellectual disability. Our understanding of the genetic architecture and neurobiology of these conditions has also increased through the use of new analytic and bioinformatic methods.1

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