Inherited Diseases
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Genetic Counselors

Genetic counselors are health professionals who are trained to help families understand genetic disorders and to provide information and support to those families. They may also serve as patient advocates by referring individuals or families to local services that can be of assistance.

Researchers can use DNA sequencing to identify variations in a person’s genome. Some variations between individuals result from epigenetic differences. These are changes in gene function, some of which can be inherited but are not the result of changes in DNA sequence. Genetic research is a powerful tool for treating medical conditions, but it is still a new tool. Many people whose families are affected by genetic disorders don't understand how it will affect their lives. Even genetic researchers and doctors don't fully understand how genes cause all genetic disorders. Genetic counselors work with doctors and families to help families get the information they need to understand the disorder.

Invite a genetic counselor to give a community talk about the role of genetic counseling, various genetic disorders, or the importance of discussing your family health history with your medical provider. You can find a genetic counselor from the website of the National Society of Genetic Counselors.

Young Readers

Book cover image of The Adventures of the Sickler  Book cover image Mallory's 65 Roses  Children's author reading My Genes Don't Fit Right Photo of author Shannon Pulaski holding her book Mom's Genes standing with her three children

  • The Adventures of the Sickler: The Transformation | Parker Todd | Scribble Scrabble Publishing | 2017 | 36 pages | ISBN: 978-0999364000
  • Mallory's 65 Roses | Diane Shader Smith | Independently published | 1997 | 24 pages | ISBN: 978-0970035301 
  • My Genes Don't Fit Right!: Understanding the genetic inheritance pattern of cystic fibrosis | Abigail McKernon | Independently published | 2019 | 27 pages | ISBN: 978-179755029
  • Mom's Genes | Shannon Pulaski | Cure Media Group, LLC | 2018 | 29 pages | ISBN: 978-099976660


We all have genes that don't work properly. In most cases, the other copy of the gene makes up for the one that does not work properly and we are healthy. A problem only arises if we meet someone else who has a non-working copy of the same gene and we have a child who inherits two non-working copies of that gene. This is called recessive inheritance.

Sometimes if one of our genes is not working properly the other copy of the gene cannot make up for it and that causes a condition or an increased risk of developing a condition. Each time we have a child we randomly pass on one copy of each gene. If the child inherits the copy that doesn't work properly, they too may develop the condition. This is called dominant inheritance.

Examples of Single Gene Disorders
Examples of Multifactorial Gene Disorders

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Terms of use: Network of the National Library of Medicine (NNLM) staff offer these health discussion resources for educational use. The materials included do not necessarily reflect the views or opinions of the author, publisher, or the sponsoring agencies of the National Library of Medicine (NLM) and the National Institutes of Health (NIH).