Get a deeper understanding of what hypochondroplasia is, how it’s diagnosed, and the ways it may impact your child’s growth, development, and health.
Hypochondroplasia is a type of skeletal dysplasia, a rare genetic condition that inhibits bone growth.
It impacts each person differently and every family’s needs are unique.
Hypochondroplasia is rare and can look different for each person, which means the journey to diagnosis can vary. Most children with hypochondroplasia are born to average-stature parents—fewer have one or both parents with the condition.
Doctors may not always be familiar with hypochondroplasia, think a child is just “naturally small,” or that their delayed growth is due to a different condition.
A hypochondroplasia diagnosis is confirmed through genetic testing, which can be the first step in getting answers to help your child and ensure they’re receiving the proper care.
It’s important to speak with your doctor about connecting with the right specialists, understanding your management options, and finding resources to support both you and your child.
Hypochondroplasia is caused by a change in a gene called fibroblast growth factor receptor 3 or FGFR3. The FGFR3 gene:
This permanent genetic change can happen in different places on the FGFR3 gene, which is one reason why hypochondroplasia can look different for each person and affect health in unique ways.
Bones grow for a limited time—before birth until late adolescence/early adulthood. No matter how the FGFR3 gene is changed in hypochondroplasia, it results in overactive FGFR3 cell signaling that causes:
In addition to affecting stature, hypochondroplasia can also impact other aspects of development such as:
The extent of these impacts will vary from person to person but can lead to delayed motor development, pain, or reduced mobility later in life.
When bone growth is inhibited, there’s less space inside the body for organs and nerves. For some people with hypochondroplasia, this can affect physical development and lead to health issues that have a lasting impact, including:
Hypochondroplasia may also be associated with neurological impacts, such as seizures, neurocognitive delay, or challenges (occurs in a smaller number of people). Additionally, some individuals and families experience emotional and social challenges.
Explore these FAQs for a deeper understanding of hypochondroplasia.
Hypochondroplasia is a type of skeletal dysplasia—a rare genetic condition that affects bone and cartilage development. Hypochondroplasia inhibits bone growth in over 90% of the bones in the body and, in a smaller number of people, can also impact brain development.
Hypochondroplasia is caused by a change in the FGFR3 gene, which, among other functions, controls how cartilage develops into bone. The change in the FGFR3 gene results in overactive FGFR3 signaling in cartilage cells, which causes inhibited bone growth throughout the body.
Hypochondroplasia is rare. Because it is often underdiagnosed and misdiagnosed, the exact number is unknown but it is estimated to occur in 1 in 15,000-40,000 people. In the US, the average age of diagnosis is around 4.5 years old.
Hypochondroplasia is a rare condition and can look and affect each person differently. Because of this, some doctors may not be familiar with hypochondroplasia. They may think that a child is just small, choosing to wait for them to grow and catch up, or they can incorrectly diagnose with another condition or miss it completely. Because of its potential health impacts, it’s important to confirm a hypochondroplasia diagnosis through genetic testing to ensure your child is receiving proper care.
Hypochondroplasia is caused by a change in the FGFR3 gene that can be passed down by parents but mostly occurs spontaneously, which explains why the majority of children with hypochondroplasia are born to average-stature parents. If 1 or both parents have hypochondroplasia, their children have a 50% or 75% (respectively) likelihood of inheriting the condition.
Hypochondroplasia inhibits bone growth throughout the body, which can lead to reduced or disproportionate growth. When bone growth is inhibited, there’s less room in the body for organs and nerves, which can impact different aspects of health and development. In addition, individuals with hypochondroplasia may experience neurological impacts or emotional and social challenges.
Be the first to access information about hypochondroplasia, including updates on the latest research, educational resources, and future events in your area. All sent directly to your inbox.
References