What is the Difference Between Genetic Disorders and Polygenic Diseases?

The main difference between genetic disorders and polygenic diseases lies in the number of genes involved and their inheritance patterns.

Genetic Disorders:

These disorders can be caused by chromosomal mutations, a combination of gene mutations, or a single gene mutation.
They follow Mendelian or non-Mendelian inheritance patterns.
Examples include cystic fibrosis and Huntington's disease, which are caused by mutations in a single gene.

Polygenic Diseases:

These diseases are influenced by the combined effects of many genes.
They often involve complex traits determined by multiple genes at different loci, without the influence of the environment.
Examples include coronary heart disease, Type 2 diabetes, Alzheimer's disease, cancer, and schizophrenia.

Both genetic disorders and polygenic diseases are due to mutations in genetic material and may show similar symptoms, such as cognitive defects and growth problems. They can be diagnosed through genetic testing and treated through surgeries and gene therapies. However, polygenic diseases are more complex and often have less clear-cut inheritance patterns compared to genetic disorders.

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What is the Difference Between Genetic Disorders and Polygenic Diseases?

Comparative Table: Genetic Disorders vs Polygenic Diseases

Here is a table comparing the differences between genetic disorders and polygenic diseases:

Feature	Genetic Disorders	Polygenic Diseases
Definition	Genetic disorders are caused by a single gene or a small number of genes.	Polygenic diseases are caused by the joint contribution of multiple independently acting genes, with the individual contribution of each gene being small or even unnoticeable.
Inheritance	Inheritance is often clear-cut and easier to predict.	Inheritance is more complex and not as clear-cut as monogenic diseases.
Prevalence	Genetic disorders are generally rare.	Polygenic diseases are more common and have a greater social and economic impact.
Testing	Monogenic diseases are easier to test for, as they involve the presence or absence of a faulty gene.	Polygenic diseases are more challenging to test for, as they involve multiple genetic variations with small effects.
Risk Assessment	Risk assessment for monogenic diseases is simpler, as it involves identifying carriers of the faulty gene.	Risk assessment for polygenic diseases is more complex, involving the calculation of a polygenic risk score based on an individual's unique genetic variations.
Examples	Examples of genetic disorders include cystic fibrosis, Duchenne muscular dystrophy, and hemophilia.	Examples of polygenic diseases include Type 2 diabetes, heart disease, and many common cancers.

In summary, genetic disorders are caused by a single gene or a small number of genes, have a clearer inheritance pattern, and are generally rarer than polygenic diseases. Polygenic diseases, on the other hand, involve the joint contribution of multiple genes, have a more complex inheritance pattern, and are more common. Testing and risk assessment for genetic disorders are simpler than for polygenic diseases, which involve more complex genetic architectures.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.