What is Mucopolysaccharidosis Type IVA (MPS4A)?
Mucopolysaccharidosis, Type IVA; MPS4A is a rare genetic metabolic disorder. It is often also referred to as Morquio syndrome.
The disease may present at birth or later age. The syndrome is progressive but may develop at either a slow or fast rate depending on the type the individual develops.
This syndrome is also known as:
Galactosamine-6-sulfatase Deficiency; GALNS Deficiency; Morquio A Disease; Morquio Syndrome A; MPS IVA; MPSIV Mucopolysaccaridosis type IV; Mucopolysaccharidosis type_IV
What are the main causes of Mucopolysaccharidosis Type IVA (MPS4A)?
The syndrome is a lysosomal storage disease caused by mutations in the GALNS gene. It is inherited in an autosomal recessive pattern.
The disease affects the body’s ability to break down the large sugar molecules known as glycosaminoglycans. The buildup of these molecules in the body tissue triggers the symptoms of the syndrome.
Autosomal recessive inheritance means an affected individual receives one copy of a mutated gene from each of their parents, giving them two copies of a mutated gene. Parents, who carry only one copy of the gene mutation will not generally show any symptoms but have a 25% chance of passing the copies of the gene mutations onto each of their children.
What are the main symptoms of Mucopolysacchardisosis Type IVA (MPS4A)?
Symptoms of the syndrome included enlarged and scarred tissues and organs.
Other possible health conditions related to the syndrome include skeletal abnormalities short stature and hearing loss, and problems relating to the eyes. Hyperflexible joints often present as a symptom.
Physical features of the syndrome include short stature, knock knees, and low muscle tone.
Possible clinical traits/features:
Restrictive ventilatory defect, Keratan sulfate excretion in urine, Chondroitin sulfate excretion in urine, Juvenile onset, Recurrent upper respiratory tract infections, Ulnar deviation of the wrist, Scoliosis, Autosomal recessive inheritance, Prominent sternum, Widely spaced teeth, Platyspondyly, Pointed proximal second through fifth metacarpals, Osteoporosis, Ovoid vertebral bodies, Wide mouth, Disproportionate short-trunk short stature, Epiphyseal deformities of tubular bones, Coxa valga, Flaring of rib cage, Coarse facial features, Constricted iliac wings, Grayish enamel, Hypoplasia of the odontoid process, Hyperlordosis, Kyphosis, Genu valgum, Hearing impairment, Opacification of the corneal stroma, Hepatomegaly, Joint laxity, Metaphyseal widening, Mandibular prognathia, Intellectual disability, Inguinal hernia, Cervical subluxation, Cervical myelopathy, Carious teeth, Abnormal heart valve morphology.
How is it diagnosed?
To find out if someone has a diagnosis of Mucopolysaccharidosis Type IVA (MPS4A), it is important to have a consultation and evaluation with a clinical genetic specialist. Specialists may also suggest specific genetic testing or other types of tests to help reach a diagnosis. FDNA’s AI technology can help speed up the diagnostic process by analyzing facial features and other health information.
