Morquio Syndrome
Description
Morquio syndrome is a rare genetic disorder that affects the body‘s ability to break down certain complex sugars. This leads to a buildup of these sugars in the body, which can cause a range of problems, including skeletal abnormalities, joint problems, and other health issues. This comprehensive guide provides information on Morquio syndrome, from recognizing the signs and symptoms to understanding its causes and available treatment options.
Genes Involved
Morquio syndrome is caused by mutations in specific genes that are responsible for producing enzymes involved in the breakdown of complex sugars. Two main types of Morquio syndrome exist, each linked to a different gene:
- Morquio A: Caused by mutations in the GALNS gene, leading to a deficiency of the enzyme N-acetylgalactosamine-6-sulfatase.
- Morquio B: Caused by mutations in the GLB1 gene, leading to a deficiency of the enzyme beta-galactosidase.
Recognizing the Signs and Symptoms
Morquio syndrome can manifest in various ways, with symptoms often appearing in early childhood. Some common signs and symptoms include:
- Skeletal Abnormalities: Short stature, disproportionately short trunk, bowed legs, prominent forehead, and a large head.
- Joint Problems: Joint pain, stiffness, and limited range of motion, particularly in the knees, hips, and elbows.
- Cardiovascular Issues: Heart valve problems and heart murmurs.
- Respiratory Problems: Enlarged tonsils and adenoids, which can lead to breathing difficulties.
- Hearing Loss: Auditory problems may occur due to bone growth abnormalities affecting the middle ear.
- Vision Problems: Eye issues like corneal clouding can arise.
- Dental Problems: Delayed tooth eruption and dental abnormalities are possible.
Causes
Morquio syndrome is an inherited genetic disorder, meaning it‘s passed down from parents to their children. It occurs when a child inherits a faulty gene from both parents, leading to a deficiency in specific enzymes required for breaking down complex sugars. These sugars then accumulate in the body, causing various health complications.
Inheritance/recurrence risk
Morquio syndrome follows an autosomal recessive inheritance pattern. This means that both parents must carry a copy of the faulty gene for their child to inherit the condition.
If both parents are carriers, there is a 25% chance with each pregnancy that their child will inherit the disorder, a 50% chance the child will be a carrier, and a 25% chance the child will not inherit the gene.
