Conclusions: This study reports a rare case of gamma-glutamylcysteine synthetase deficiency in a 4.11-year-old Arab-Muslim boy from Israel who presented with severe anemia at 2 days old, aiming to document the first such case in the Middle East and contribute to the medical literature on this extremely rare condition that has only been detected in nine patients worldwide. The gene discussed is GCLC; the disease is hyperinsulinemic hypoglycemia, familial, 4.