Gene Mutations A to Z (Or at Least the Ones You Should Know About)

Written By: Kirsten Walker

Published At: October 28, 2025

Our DNA is like an instruction manual that tells our bodies how to grow, function, and repair. But sometimes, “typos” appear in those instructions. These typos are called gene mutations—changes in our DNA sequence that can have little effect, major consequences, or anything in between.

At Seeking Health, founded by Dr. Ben Lynch, our mission is to educate and empower you to understand your health at the genetic level. This guide breaks down what gene mutations are, why they happen, and which ones you should know about.

What Is a Mutation in Genes?

A gene mutation is a change in the DNA sequence that makes up a gene(1). Mutations can be:

Inherited (passed down from parents)
Acquired (caused by environmental factors, like UV radiation, chemicals, or errors during cell division)

Some mutations are harmless, others increase disease risk, and some can even be beneficial by giving the body an advantage.

What Causes Gene Mutations?

Mutations happen for a variety of reasons:

Spontaneous errors during DNA replication
Environmental factors such as radiation, toxins, or viruses
Inherited changes that run in families(2)

What Are the Different Types of Gene Mutations?

Scientists group gene mutations into four main categories:

Substitution – One DNA base is swapped for another.
Insertion – Extra DNA bases are added.
Deletion – DNA bases are removed.
Frameshift – Insertions or deletions that disrupt how the code is read.

Together, these changes can alter how proteins are made—or stop them from working altogether.

What Is the MTHFR Mutation?

One of the most commonly discussed mutations is in the MTHFR gene (3). MTHFR (methylenetetrahydrofolate reductase) helps process folate and convert it into a usable form for methylation—a critical process for detox, energy, and neurotransmitter balance.

Two common variants are:

C677T – Often linked to higher homocysteine levels and cardiovascular concerns.
A1298C – May affect neurotransmitter balance and detox pathways.

Which is worse? C677T is generally considered more impactful, especially in a double copy (homozygous) form, though both can affect health depending on diet and lifestyle.

Is Tibia Dychodrophia a Gene Mutation?

Yes—tibia dyschondroplasia (sometimes miswritten as tibia dychodrophia) is linked to genetic factors in bone development, often studied in poultry but relevant to bone growth disorders in humans as well.

What Are 10 Examples of Gene Mutations?

Here are some well-known mutations across health and disease research:

MTHFR – Folate metabolism and methylation issues
BRCA1/BRCA2 – Breast and ovarian cancer risk (4)
CFTR – Cystic fibrosis
APOE4 – Increased Alzheimer’s risk
Factor V Leiden – Blood clotting disorders
Sickle Cell Mutation (HBB gene) – Sickle cell anemia
Huntingtin (HTT gene) – Huntington’s disease
G6PD Deficiency – Red blood cell breakdown under stress
PKU (PAH gene) – Phenylketonuria, a metabolic disorder
Lactase Persistence/Deficiency – Ability (or inability) to digest lactose

What Are 5 Harmful Mutations?

Some gene mutations are especially harmful because they disrupt critical functions:

BRCA1/BRCA2 – Strongly tied to cancer risk
CFTR – Causes cystic fibrosis
HBB gene – Leads to sickle cell disease
HTT gene – Causes Huntington’s disease
FBN1 gene – Linked to Marfan syndrome (connective tissue disorder)

How Many Gene Mutations Are There?

It’s estimated that every person carries 4–5 million genetic variants. Not all are harmful—many are neutral or even protective. But thousands have been studied and linked to specific health traits or conditions.

Putting It All Together

Gene mutations are part of what makes us unique. Some increase health risks, others are neutral, and a few even provide advantages. By learning about them, we gain tools to make smarter choices in lifestyle, nutrition, and healthcare.

For example, if you carry the MTHFR mutation, choosing active forms of folate may support better methylation. If you have clotting mutations, your provider may recommend preventive lifestyle changes.

Methyl B12 with L-Methylfolate

L-Methylfolate

Bottoms Line

Gene mutations are changes in DNA that can be inherited or acquired.
Not all mutations are harmful—some are neutral or beneficial.
MTHFR, BRCA, CFTR, and APOE are among the most studied mutations.
Understanding your genetic blueprint can help you make more personalized health decisions.

Want to go deeper? At Seeking Health, we provide resources and science-backed supplements designed with genetics in mind—so you can use your DNA knowledge as a foundation for better health.

^†These statements have not been evaluated by the Food and Drug Administration (FDA). This product is not intended to diagnose, treat, cure, or prevent any disease.