Mutations in P4HTM gene cause congenital malformations (birth defects) – the most common features are in bold text:
General:
• Global developmental delay (100% of cases)
• Obesity (53% of cases)
Brain and central nervous system:
• Intellectual disability
• Decreased muscle tone (100% of cases)
• Dysautonomia (Dysfunction of the nerves that regulate nonvoluntary body functions, such as heart rate)
• Epilepsy (50% of cases)
• Brain abnormalities on Magnetic Resonance Imaging (MRI) (53.8% of cases)
o Abnormal white matter of the brain
o Brain atrophy (loss of brain neurons and the connections between them)
Respiratory:
• Decreased rate of breathing (65% of cases)
• Sleep apnea
• Recurrent infections of the lung
Abdomen
• Gastrointestinal reflux disease (GERD)
• Constipation
Skeletal:
• Scoliosis (abnormal curvature of the spine)
Head and Neck:
• Mild malformations involving the face
• Abnormalities of the eye, including poor vision and nystagmus (occasional involuntary rapid eye movement) and cataract
P4HTM