Achondroplasia
Description
Achondroplasia is a genetic disorder that affects bone growth, leading to the most common form of dwarfism. This blog explores the complexities of achondroplasia, covering its causes, symptoms, diagnosis, management, and the incredible resilience of individuals living with this condition. We‘ll delve into the genetic underpinnings of achondroplasia, discuss how it‘s inherited, and highlight the ways individuals with achondroplasia can thrive and lead fulfilling lives.
Genes Involved
Achondroplasia is caused by a mutation in the FGFR3 gene. This gene plays a critical role in bone development, and a mutation in FGFR3 leads to abnormal bone growth. Specifically, a mutation in the FGFR3 gene results in overactive signaling, which inhibits cartilage growth and ultimately leads to the characteristic bone growth pattern seen in achondroplasia.
Recognizing the Signs and Symptoms
Achondroplasia is characterized by a distinctive set of features, including:
- Short stature: Individuals with achondroplasia have disproportionately short limbs, especially the arms and thighs, while their torsos are relatively normal in size.
- Large head: The head is often larger than average, with a prominent forehead and a slightly flattened bridge of the nose.
- Short fingers: The fingers are typically short and broad, with a distinctive trident hand shape.
- Bowed legs: The legs often bow inward, particularly in childhood.
- Limited range of motion: The joints, especially the elbows and hips, may have limited mobility.
These symptoms can vary in severity from person to person.
Causes
Achondroplasia is caused by a spontaneous mutation in the FGFR3 gene. This means that the mutation is not inherited from parents but occurs randomly during the formation of the egg or sperm cell. In most cases, the mutation is not present in either parent, and the risk of having another child with achondroplasia is very low.
Inheritance/recurrence risk
While most cases of achondroplasia are caused by spontaneous mutations, it can be inherited in some cases. If one parent has achondroplasia, there is a 50% chance that their child will also inherit the condition. If both parents have achondroplasia, there is a 75% chance that their child will inherit the condition. It‘s important to note that the severity of achondroplasia can vary even among family members who inherit the same mutation.
