PHIP mutations are linked to Chung–Jansen syndrome, a neurodevelopmental disorder characterized by global developmental delay, intellectual disability, dysmorphic facial features, and obesity.[17] These mutations are typically de novo and exhibit overlapping yet variable phenotypes, primarily affecting neurological, craniofacial, somatic, and organ systems.[18] The patient in this case presents with short stature, low body weight, mild intellectual impairment, and hyperextensible finger joints with immobile distal interphalangeal joints: features likely resulting from the PHIP deletion. The gene discussed is PHIP; the disease is obesity disorder.