In family X, a p.P368A mutation was found in the mother and a daughter (Patient II-I) with a broad clinical picture, ranging from migraine type headache, chronic constipation, poor appetite, recurrent fever, proteinuria, postural orthostatic tachycardia syndrome, atypical compound melanocytic nevi (BRAFV600E mutation with retained BAP-1 expression), and to elevated hemoglobin A1C at 5.8% and fasting glucose of 104. This evidence concerns the gene BAP1 and postural orthostatic tachycardia syndrome.