Growth
Restricted growth before birth, short stature, obesity.
Face and Head
Thin and fine hair, thick eyebrows, narrow eyes, prominent nose, underdeveloped middle face, underdeveloped upper jaw, short space between the nose and upper lip, thin upper lip, narrow mouth, small and/or widely spaced teeth, protruding jaw, small and low-set ears, deafness, short neck.
Heart
Birth defects in the heart, blockages in the heart (narrowed aorta, heart vessel problems), fluid around the heart or scarring, high blood pressure (in the body and/or lungs).
Breathing
Narrowing of the throat and windpipe, difficulty breathing, sleep problems.
Genitals
Undescended testicles, urethra problems, menstrual issues, early puberty.
Digestive System
Feeding problems in babies, constipation, difficulty swallowing, acid reflux.
Muscles and Bones
Large muscles, wide ribs, stiff joints, thick skull, spine problems, curved spine, fused vertebrae, small pelvic bones, short arms and legs, cone-shaped bone ends, short fingers, bent fingers, bent toes, toes overlapping.
Skin
Thick, stiff skin, scars that are similar to keloids.
Brain and Behavior
Mild to moderate intellectual disability, developmental delays, seizures, autism spectrum disorder, attention-deficit/hyperactivity disorder.
Cancer
While only a few patients have been reported with cancer, the risk of cancer in Myhre Syndrome is not well understood.
Causes of Death
Breathing problems from narrowed airways, serious heart conditions, severe scarring around the heart, high blood pressure in the lungs.
SMAD4