Duchenne muscular dystrophy (DMD) is a genetic condition that primarily affects people assigned male at birth. However, due to the condition’s X-linked inheritance pattern, only people assigned female at birth can be carriers of DMD.
Duchenne muscular dystrophy is a genetic condition that leads to progressive muscle weakness and degeneration. It’s caused by mutations in the DMD gene, which carries the instructions for making the protein dystrophin.
Approximately 70% to 80% of people with DMD inherit a genetic mutation that causes the condition from a biological parent who is a carrier. In the remaining 20% to 30% of people, the genetic mutation occurs early on during embryonic development and isn’t related to genetics.
A note on sex and gender
At points in this article, we use “female and male” to refer to birth-assigned sex, and “mother and father” to refer to genetic parentage related to birth-assigned sex (unless quoting from sources using nonspecific language).
Birth-assigned sex is typically determined by chromosomes, and gender is a social construct that can vary between time periods and cultures. Both of these aspects are acknowledged to exist on a spectrum both historically and by modern scientific consensus.
To understand what it means to be a carrier of DMD, it’s important to understand some baseline genetic patterns.
Typically, people
Within each set of 23 chromosomes from a genetic parent is a sex chromosome — Y or X. The pairing you receive from your two genetic parents determines your birth-assigned sex.
People assigned female at birth typically have the sex chromosomes XX, and those assigned male at birth typically have the sex chromosomes XY. Intersex people may have different combinations of chromosomes, like XXY.
People born with XY sex chromosomes can pass on either an X or a Y, and people with an XX pairing — and no Y — can only pass on an X.
How can people be carriers of DMD?
“Carriers” are people who have one copy of a gene with a mutation that causes a recessive condition like DMD. A person who carries the condition won’t show many — or possibly any — symptoms because they have a second, functional copy of the gene.
Recessive conditions typically require a person to have two copies of a mutation to cause the condition. The exception to this are X-linked recessive conditions like DMD, which result from a mutation on the X chromosome.
Because people assigned male at birth typically only have one X chromosome, if a mutation related to a condition is present on that chromosome, the condition fully develops.
People assigned female at birth typically have two X chromosomes. Even if they inherit one X chromosome with a mutation related to DMD, having the other X chromosome without the mutation is often enough to prevent symptoms related to low dystrophin production. This means that only people assigned female at birth can be carriers of DMD.
Each time a person who is a carrier of DMD has a child who is assigned male at birth, the child has a 50% chance of developing DMD. A child assigned female at birth will have a 50% chance of being a carrier.
It’s possible for carriers of DMD to experience symptoms related to low dystrophin production if the chromosome without a DMD mutation becomes
Doctors may refer to people who experience this as “manifesting carriers” because they manifest symptoms of DMD despite having an unaffected gene.
In people assigned female at birth, either genetic parent can pass on a DMD mutation on an X chromosome.
Because people assigned male at birth can typically only inherit a Y chromosome from a parent who was also assigned male at birth, they can only inherit an X chromosome with a DMD mutation from a parent who was assigned female at birth.
People assigned male at birth can’t be carriers of DMD without manifesting symptoms of the condition. If they inherit a DMD mutation on their X chromosome, they will develop symptoms of dystrophin deficiency because they don’t have a second gene to override it.
Genetic testing can analyze the DNA of your cells to screen for known variations in the DMD gene. Geneticists look for known deletions (sections of missing DNA) and duplications (copied and repeated parts of a DNA section) on the DMD gene.
If you were assigned female at birth, testing positive for a mutation known to cause DMD confirms your carrier status.
But, because scientists haven’t yet discovered all the DMD-causing genetic variations, it’s possible to be a carrier of DMD but not test positive for a genetic variation.
Several reproductive options exist for people who carry a DMD mutation and want to start a family. These options may include having a “natural” birth, which is how some people describe a pregnancy that does not involve IVF.
Natural birth
Being a carrier of DMD does not affect your ability to carry or deliver children. If a person with a DMD mutation gives birth to a child who is assigned female at birth, the child will have a 50% chance of being a DMD carrier. A child who is assigned male at birth will have a 50% chance of having DMD.
Preimplantation genetic testing
People who want to avoid passing on a DMD mutation may choose to undergo preimplantation genetic testing (PGT), which is a procedure doctors use alongside in vitro fertilization (IVF).
IVF involves fertilizing eggs with sperm outside of someone’s body in a laboratory. Typically, IVF creates multiple embryos. Doctors can then use PGT to screen the DNA of those embryos for a DMD mutation before implantation in the uterus. Only embryos that test negative through PGT would be candidates for the final stages of IVF.
PGT isn’t infallible, though. According to a 2023 literature review, there may be unknown or small duplications or deletions PGT can’t detect in certain genetic conditions. It’s also not a guarantee that IVF will lead to a pregnancy.
Adoption
People who don’t want to pass on a DMD mutation might also consider adopting a child, which can be a highly rewarding experience. There are currently more than 100,000 children waiting for adoption in the United States.
Egg or sperm donation
Another option people may consider along with IVF is using a donor sperm or egg from someone who is not a carrier or affected by DMD.
If you’d like to learn more about being a DMD carrier, you can visit or contact the following organizations:
Duchenne muscular dystrophy (DMD) is a genetic condition that primarily affects people assigned male at birth.
People typically inherit DMD. It’s an X-linked recessive condition, which means DMD gene mutations occur on the X sex chromosome.
Due to sex inheritance patterns, only people with two X chromosomes — who are typically assigned female at birth — can be carriers of DMD. People assigned male at birth with a DMD mutation on their X chromosome will develop DMD.