But first, what is a gene anyway?

Take a closer look at the instruction manual for the human body

You’ve probably heard about genes and how you got your hair color from one biological parent and your eye color from the other. But there is so much more to genetics and how genes work in the body.


The job of the gene

The key role of genes is to provide the instructions for making proteins. Proteins are the building blocks of the body and serve important functions like tissue repair and helping blood to clot.

What causes genetic conditions?

How mutations, or variations, can lead to genetic conditions

Did you know there are approximately 20,000 genes in the human genome? A mutation, or permanent variation, in just one gene can lead to a genetic condition. Knowing what causes a genetic condition is the first step in understanding how, potentially through ongoing research in gene therapy, healthcare providers might be able to treat these conditions differently.

Mutations can affect your genetic instructions

A mutation can affect the genetic instructions in your body. The instructions can be missing or incorrect, changing the way proteins are produced. This can result in the production of a protein that does not work properly or, in some cases, the protein is not produced at all.

Mutations can take the form of changed nucleotide pairings, extra DNA where it doesn’t belong, missing DNA, or repeated DNA.

In people with hemophilia A or B, the genetic mutation affects the body’s ability to produce a protein called factor VIII or factor IX, respectively. These proteins are critical for blood to clot.

There are three types of genetic conditions

The 3 types of genetic conditions are single-gene conditions, multi-gene conditions, and chromosomal conditions.

  1. Monogenic conditions
    Monogenic conditions—like hemophilia—are caused by a mutation in a single gene. Other examples include cystic fibrosis and Huntington’s disease
  2. Multifactorial inheritance conditions
    Multifactorial inheritance conditions, or multi-gene conditions, develop from multiple small genetic mutations and can lead to some of the more common diseases we’re familiar with, such as heart disease and diabetes
  3. Chromosome disorders
    Chromosome disorders are caused by changes to the number or structure of chromosomes. Down syndrome is the most common disorder related to this type of abnormality

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