Medical Genetics is a medical specialty made up of clinical geneticists who are physicians certified in multiple clinical specialties. The Department of Medical Genetics at Mayo Clinic is complemented by comprehensive on-site laboratory genetics services. The knowledge that patients gain from a visit to Mayo's Department of Medical Genetics may help them plan a family, obtain better treatment for a medical condition, or improve their understanding of how a genetically based disorder affects them and their family.

The role of geneticists in caring for patients is expanding, as researchers identify genes that may indicate whether patients may inherit or develop certain diseases. For instance, the Department of Medical Genetics is involved with the Mayo Clinic Cancer Center to assess patient risk for developing breast and colon cancers; genetic information is used to guide efforts in medical screening and preventive treatment.

Disorders addressed by clinical genetists include all age groups and types of conditions. The clinical geneticist takes on varying roles, including the diagnosis, management, treatment, and patient counseling for these conditions, which may include:

  • Rare single-gene disorders
  • Birth defects
  • Familial cancer
  • Metabolic disorders
  • Neurologic disorders
  • Multisystem disorders

What is Medical Genetics?

Medical Genetics is concerned with how genes and heredity affect human health. Hundreds of disorders are genetically based, including hemophilia (a blood disorder), cystic fibrosis (a lung and digestive system disorder) and achondroplasia (a growth disorder).

In virtually all cells of a person's body are 46 packages of genetic material (chromosomes). Each chromosome consists of a long chain of special chemicals called DNA (deoxyribonucleic acid). A gene is a segment of one DNA chain. Genes are linked together on this chain of DNA, and each one has a specific "address" on the chromosome. For example, the gene that controls eye color occurs in the same spot on the same chromosome in each human being.

This knowledge allows scientists to map the location of genes and identify their function. Each chromosome contains thousands of genes. In recent years, scientists have identified the genes that cause many disorders. Genetic disorders result from abnormalities — or mutations — in a person's DNA. These abnormalities are formed by the erroneous addition, deletion or substitution of chemicals that make up DNA. Mutations can occur spontaneously, or they can be inherited. Mutations can also be caused by the environment; for example, from exposure to chemicals or radiation. The Department of Medical Genetics is widely recognized for its outstanding research contributions. Read more about research in the Department of Medical Genetics.

Read more about genetic testing at
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