Prenatal Screening for Duchenne Muscular Dystrophy

For parents, nothing is more important than the health of their baby. Every detail counts, from extra care towards what the baby ingests to how homes are baby-proofed. What about your baby’s genetics? Many parents often overlook the importance of genetic inheritance.

Genetic disorders are more common than people think, and one genetic disorder is Duchenne muscular dystrophy (DMD). Prenatal screening tests are available for parents to use to help determine if their baby has or is at risk of inheriting DMD. If you are curious about what DMD is and what DMD prenatal screening involves, look at everything you need to know below!

A brief overview

DMD is the loss of muscle strength and function over time and affects skeletal and heart muscles. This genetic disorder is more common in males than females. The onset age is typically between two and eleven years old. Early signs of DMD include delayed ability to sit, stand, walk, and speak. 

Possible symptoms of DMD at or after onset include:

• Cardiomyopathy
• Calf muscle hypertrophy
• Cognitive impairment
• Delayed speech and language development
• Flexion contracture
• Global developmental delay
• Motor delay
• Progressive muscle weakness
• Proximal muscle weakness
• Respiratory insufficiency
• Scoliosis
• Skeletal muscle atrophy
• Specific learning disability
• Waddling gait
  

DMD is caused by the inheritance of genetic variants (changes in the typical DNA sequence or genetic code). Specifically, the variant is pathogenic, affecting how the gene works. This is also known as a mutation (disease-causing variant).

What does the test involve?

Prenatal genetic testing for DMD involves two methods: chorionic villus sampling (CVS) and amniocentesis. CVS is usually performed between 11-14 weeks of gestation and removes tissue (samples) from the placenta. 

The test is performed by one of two methods.

• Transcervical CVS – Insertion of forceps into the cervix.
• Transabdominal CVS – Insertion of a needle through the female’s abdomen (the most common method of CVS)
  

Amniocentesis is performed later, usually at 15-16 weeks of gestation. This method is similar to transabdominal CVS but retrieves amniotic fluid where cells are accessible. New tests are underdevelopment that takes the baby’s DNA from the female biological parent in non-invasive prenatal diagnosis (NIPD). Families using in vitro fertilization (IVF) can have a pre-implantation genetic diagnosis (PGD). PGD tests early embryos to select unaffected embryos for possible fertilization carefully.

How to find out if you're a carrier

‍

For children of female carriers, male children have a 50% chance of being affected, and female children have a 50% of becoming carriers (resource 4). Therefore, it is essential to identify if you are a potential carrier. Most often, DMD carriers are not symptomatic. One clue if you or your partner may be carriers is to see if you or their family has a medical history of DMD or positive tests for carriers. The most effective way to see if your genes show carrier indicators is to perform a genetic test (usually through blood draws).

What are the risk factors?

‍

As previously mentioned, CVS and amniocentesis are DMD's primary prenatal screening methods. Although both ways serve a purpose for early detection benefits, there are associated risks. Both approaches pose a small risk of causing a miscarriage. Additionally, there are instances of misleading results. Therefore, it is vital to consult a genetic doctor to determine what is best for your family.

Treatment options for DMD

Although DMD is presently incurable, various treatments exist, primarily medication and therapy. A muscle protein called dystrophin experiences problems with DMD. Multiple medications are available to help increase dystrophin levels. Research is also studying glutamine and dietary supplement creatine to see their effects on the production and storage of muscle energy. 

DMD symptoms can also be treated with:

• Physical therapy
• Exercise
• Rehabilitative devices
• Surgery
• Respirator care

Stem cell therapy for DMD

Support shows that stem cell therapy can help treat DMD. Since DMD is a degenerative disorder of cells, stem cell implants can provide a new supply of or regenerate cells. The new cells carry vital muscle protein that a person’s body is missing because DMD mutated their natural protein. Research by a leading doctor from Japan discovered that something miraculous occurs by building nucleic acid (what makes DNA) from new stem cells. The nucleic acid binds to the mutated protein. However, its genetic code ‘skips’ the mutation, resulting in functional cells without faulty components. Research on stem cells and DMD is still underway, but it is promising to show that stem cell transplants offer hope for those affected by DMD.

Bank your stem cells with Anja Health

The world of parenting is challenging, and many parents face the challenges of keeping their children healthy and safe. Helping kids live healthily begins while they are in the womb. Genetic prenatal screening helps parents know what to expect and what type of genetic disorders their children may inherit. Currently, DMD is not curable, but treatment options and screening are available to help determine the best plan for those affected.

‍
Your plan should begin by banking stem cells through cord blood banking. Cord blood offers a precious supply of stem cells that can later be used to help treat genetic disorders in your children. Start your path of preserving your vital stem cells by contacting Anja Health to see how you can begin your banking process.