Advanced Topics
In a nutshell: Genetic disorders are caused by changes in DNA, affecting individuals and families.
## What Are Genetic Disorders?
Genetic disorders are diseases caused by changes or mistakes in genes or chromosomes.
## Types of Genetic Disorders
- **Single-gene disorders**: Caused by changes in one gene (e.g., cystic fibrosis).
- **Chromosomal disorders**: Caused by changes in chromosomes (e.g., Down syndrome).
- **Multifactorial disorders**: Caused by a combination of genetic and environmental factors (e.g., heart disease).
## How Are They Inherited?
Some genetic disorders are inherited in a predictable way (dominant or recessive), while others are more complex.
## Diagnosis and Treatment
- Genetic testing can identify many disorders before symptoms appear.
- New treatments like gene therapy offer hope for curing or managing these conditions.
## Why Study Genetic Disorders?
Learning about these disorders helps doctors diagnose and treat patients, and helps families understand their health risks.
Examples
- A person inherits sickle-cell disease because both parents passed on the sickle-cell gene.
- Down syndrome occurs when there is an extra copy of chromosome 21.