Genetic Disorders: What Are They, Types, Symptoms & Causes (2024)

What are genetic disorders?

Genetic disorders occur when a mutation (a harmful change to a gene, also known as a pathogenic variant) affects your genes or when you have the wrong amount of genetic material. Genes are made of DNA (deoxyribonucleic acid), which contain instructions for cell functioning and the characteristics that make you unique.

You receive half your genes from each biological parent and may inherit a gene mutation from one parent or both. Sometimes genes change due to issues within the DNA (mutations). This can raise your risk of having a genetic disorder. Some cause symptoms at birth, while others develop over time.

Genetic disorders can be:

• Chromosomal: This type affects the structures that hold your genes/DNA within each cell (chromosomes). With these conditions, people are missing or have duplicated chromosome material.
• Complex (multifactorial): These disorders stem from a combination of gene mutations and other factors. They include chemical exposure, diet, certain medications and tobacco or alcohol use.
• Single-gene (monogenic): This group of conditions occurs from a single gene mutation.

What are common genetic disorders?

There are many types. They include:

Chromosomal disorders

• Down syndrome (Trisomy 21).
• FragileX syndrome.
• Klinefelter syndrome.
• Triple-X syndrome.
• Turner syndrome.
• Trisomy 18.
• Trisomy 13.

Multifactorial disorders

• Late-onset Alzheimer’s disease.
• Arthritis.
• Autism spectrum disorder, in most cases.
• Cancer, in most cases.
• Coronary artery disease.
• Diabetes.
• Migraine headaches.
• Spina bifida.
• Isolated congenital heart defects.

Monogenic disorders

• Cystic fibrosis.
• Deafness that’s present at birth (congenital).
• duch*enne muscular dystrophy.
• Familial hypercholesterolemia, a type of high cholesterol disease.
• Hemochromatosis (iron overload).
• Neurofibromatosis type 1 (NF1).
• Sickle cell disease.
• Tay-Sachs disease.

Are there other types of genetic disorders?

Genetic disorders may also cause rare diseases. This group of conditions affects fewer than 200,000 people in the U.S. According to experts, there may be as many as 7,000 of these diseases.

Rare genetic disorders include:

• AA amyloidosis.
• Adrenoleukodystrophy (ALD).
• Ehlers-Danlos syndrome.
• Mitochondrial diseases.
• Usher syndrome.