The landscape of Duchenne is rapidly changing!

New therapies are being developed, some of which will help any person with Duchenne, while others depend on the person's genetic change, or mutation. Knowing the mutation is important, as it can affect decision-making about the possible use of new therapies and entering into clinical trials.

Duchenne is caused by changes (mutations) within the dystrophin gene. A gene is made up of coding regions call "exons," and the areas in between exons called "introns." Dystrophin has 79 exons, which makes it the largest gene in the body.

Genetic testing can identify your/your child's specific mutation. If you/your child need genetic testing, please talk with your doctor, genetic counselor, or one of the The Duchenne Registry genetic counselors.

Making the dystrophin protein from the gene involves several steps. One of the first steps is removing the introns and fitting the exons together, 1-79, like puzzle pieces.

exon map of the dystrophin gene

If there is a missing piece within the dystrophin gene (deletion) or an extra piece (duplication), your body can have difficulty making dystrophin. The most common genetic mutation causing Duchenne is a deletion, where part of the gene is missing.

One approach that strives to address this lack of dystrophin is exon skipping, which tells the body to hide an exon next to the missing piece, so the whole section can be skipped over and the remaining exons can fit together. The intent is to allow the body to make a shorter form of the dystrophin protein. The tool below will help you to know whether your/your child's genetic mutation might benefit from an exon skipping therapy.

missing exon

skipped exon

Exon deletion tool

If you know your/your child's genetic change (mutation) is an exon deletion, this educational tool can help you understand if you/your child may be a candidate for an exon skipping therapy. If you are unsure of your/your child's mutation, or if you are confused by your/your child's genetic test results you've received, please contact one of our genetic counselors to learn more.

Call 888-520-8675 or email

Instructions: Enter the first and last number correlating to your child's deletion in the fields below. If a single deletion, enter the same number in both fields.
Example: 12-12, 12-14, 12-75.

enter
first exon
deleted
to
enter
last exon
deleted

Based on the information you entered, there may be a treatment option available for you/your child that skips exon {number}. Talk to your local doctor or genetic counselor to learn more. You may also contact one of our genetic counselors at 888-520-8675 or .

Based on the information you entered, you/your child may be a candidate for mutation-specific therapies in clinical trials that skip exon {number}. Talk to your local doctor or genetic counselor to learn more. You may also contact one of our genetic counselors at 888-520-8675 or .

Based on the information you entered, you/your child may be a candidate for future mutation-specific clinical trials that skip exon {number}. Talk to your local doctor or genetic counselor to learn more. You may also contact one of our genetic counselors at 888-520-8675 or .

Based on the information you entered, this genetic change is either not amenable to exon skipping or is not supported by this tool, as it may be a different type of mutation (e.g., duplication, stop codon, etc.). Please try again, or speak with your local doctor or genetic counselor for more information. You may also contact one of our genetic counselors by calling 888-520-8675 or emailing us at .

Based on the information you entered, you/your child would need skipping of both exon {number}. There are FDA-approved treatment options for skipping first alone or second alone, but these have not been tested in combination. Researchers do not know whether two exon skipping therapies in combination would provide any clinical benefit. Please speak with your local doctor or genetic counselor for more information. You may also contact one of our genetic counselors by calling 888-520-8675 or emailing us at .

Based on the information you entered, there is an FDA-approved treatment option available that skips exon {number}. However, this deletion involves the beginning of the gene (the actin binding domain) and may not benefit from exon skipping. Talk to your local doctor or genetic counselor to learn more. You may also contact one of our genetic counselors by calling 888-520-8675 or emailing us at .

Based on the information you entered, there is an FDA-approved treatment option available that skips exon {number}. However, this deletion is very large (involving more than 35 exons) and may not benefit from exon skipping. Talk to your local doctor or genetic counselor to learn more. You may also contact one of our genetic counselors by calling 888-520-8675 or emailing us at .

Based on the information you entered, there is an FDA-approved treatment option available that skips exon {number}. However, this deletion involves the end of the gene (the dystroglycan binding domain) and may not benefit from exon skipping. Talk with your local doctor or genetic counselor to learn more. You may also contact one of our genetic counselors by calling 888-520-8675 or emailing us at .

Based on the information you entered, there is an FDA-approved treatment option available that skips exon {number}. Talk with your local doctor or genetic counselor to learn more. You may also contact one of our genetic counselors by calling 888-520-8675 or emailing us at .

Based on the information you entered, you/your child may be a candidate for future mutation-specific clinical trials that skip exon {number}. However, this deletion involves the beginning of the gene (the actin binding domain) and may not benefit from exon skipping. Talk to your local doctor or genetic counselor to learn more. You may also contact one of our genetic counselors by calling 888-520-8675 or emailing us at .

Based on the information you entered, you/your child may be a candidate for future mutation-specific clinical trials that skip exon {number}. However, this deletion involves the end of the gene (the dystroglycan binding domain) and may not benefit from exon skipping. Talk with your local doctor or genetic counselor to learn more. You may also contact one of our genetic counselors by calling 888-520-8675 or emailing us at .

Based on the information you entered, you/your child may be a candidate for future mutation-specific clinical trials that skip exon {number}. However, this deletion is very large (involving more than 35 exons) and may not benefit from exon skipping. Talk to your local doctor or genetic counselor to learn more. You may also contact one of our genetic counselors by calling 888-520-8675 or emailing us at .

This educational tool is designed to provide information about exon deletions only, which is not meant to be used as the basis for diagnosis or deciding upon any course of treatment for Duchenne. This tool does not include point mutations or other small mutations, duplications, or multiple deletion ranges (e.g., 14-19 and 37-50). Be sure to speak with your child's doctor or genetic counselor about your child's genetic testing results.