LAMA5 syndromes are due to the alteration of laminin alpha 5 chain, a protein that interacts with several other proteins and regulates their distribution in many organs and tissues.
The main clinical symptoms classified by organ involved are the following:
Growth parameters and developmental anomalies
Height and weight are in the lower percentiles from early infancy to adolescence. Head circumference can be reduced. Reduction of muscle tone with crying, sucking, feeding and respiratory problems can occur. Mental development is normal.
Malformative features
Form inherited from both parents: elongated face, eyelid dropping, mild presence of facial hair, severe scoliosis.
Form inherited from one parent: mild baldness, dry and brittle hair, lack of eyebrows, dental abnormalities, mild to severe scoliosis.
Neurological features
Form inherited from both parents: reduced muscle tone, inability to walk, eyelid drooping; facial, tongue, palate, limbs muscles weakness, marked fatigue during exercise.
Form inherited from one parent: muscle pain and fatigue, waddling gait, hollow back condition.
Ocular findings
Mild dropping of eyelids, unreal appearance of abnormal protrusion of eyeball, night blindness.
Bone, joint and skeletal findings
Form inherited from both parents: severe scoliosis, articular flexion contractures.
Form inherited from one parent: mild to severe scoliosis, joints pain, arthritis, articular cartilage erosion and joint effusions, temporomandibular joint dysfunction, joint hypermobility.
Gastrointestinal features
Form inherited from one parent: Internal organs and rectal prolapse, haemorrhoids, intestinal malabsorption, chronic/recurrent gastritis, lactose intolerance and celiac like-syndrome.
Endocrinological features
Low thyroid hormones, abnormal response to insulin hormone.
Urogenital features
Floating kidney, uterine fragility/rupture, pelvic prolapse.
Skin abnormalities
Mild baldness, scarring defects.