How can gene variants affect health and development?
Gene variants can alter or eliminate protein function, disrupting development and leading to genetic disorders.
Overview
Each cell relies on thousands of proteins to perform specific tasks at precise times and locations. When a gene variant (also called a mutation) changes the instructions for making a protein, the resulting protein may malfunction or fail to be produced. If the affected protein plays a critical role in the body, normal development can be disrupted or a health condition may arise. A condition caused by variants in one or more genes is termed a genetic disorder.
Impact of Severe Variants
Some gene variants are so severe that they prevent an embryo from surviving to birth. These changes occur in genes essential for early development and typically disrupt embryonic formation at its earliest stages. Because the effects are extremely serious, such variants are considered incompatible with life.
Clarifying Common Misconceptions
It is important to understand that genes themselves do not cause disease; rather, genetic disorders result from variants that alter or eliminate a gene’s function. For example, when people refer to someone having “the cystic fibrosis gene,” they are usually describing a version of the CFTR gene that contains a disease‑causing variant. Everyone, including individuals without cystic fibrosis, possesses a version of the CFTR gene.
Further Resources
The National Human Genome Research Institute (NHGRI) offers an introduction to genomics.
The Centers for Disease Control and Prevention (CDC) provides basic genetic concepts.
The Centre for Genetics Education offers a fact sheet about genetic changes.
Topics in the “Variants and Health” Chapter
- What is a gene variant and how do variants occur?
- How can gene variants affect health and development?
- Do all gene variants affect health and development?
- What kinds of gene variants are possible?
- Can a change in the number of genes affect health and development?
- Can changes in the number of chromosomes affect health and development?
- Can changes in the structure of chromosomes affect health and development?
- Can changes in noncoding DNA affect health and development?
- Can changes in mitochondrial DNA affect health and development?
- What are complex or multifactorial disorders?
- What does it mean to have a genetic predisposition to a disease?
- How are gene variants involved in evolution?
- What information can statistics provide about a genetic condition?
- How are genetic conditions and genes named?
Related Content
Other chapters in “Help Me Understand Genetics.”p>