An extremely rare syndrome which is characterized by hypoplastic amelogenesis imperfecta (hypoplastic dental enamel) and nephrocalcinosis (precipitation of calcium salts in renal tissue). Oral manifestations include yellow and misshaped teeth, delayed tooth eruption, and intrapulpal calcifications. Nephrocalcinosis is often asymptomatic but can progress during late childhood or early adulthood to impaired renal function (e.g. recurrent urinary infections and renal tubular acidosis), and rarely to end-stage renal failure. The disease is Monarch Disease Ontology identifier MONDO_0008771 (amelogenesis imperfecta type 1G). Also known as: AI1G, AIGFS, ERS, FAM20A amelogenesis imperfecta, amelogenesis imperfecta and gingival fibromatosis syndrome, amelogenesis imperfecta caused by mutation in FAM20A, amelogenesis imperfecta hypoplastic with nephrocalcinosis, amelogenesis imperfecta type IG.