LEOPARD Syndrome Caused by Tyr279Cys Mutation in the PTPN11 Gene.

LEOPARD syndrome (LS) is an acronym consisting of lentigines, electrocardiographic abnormalities, ocular hypertelorism, pulmonary valve stenosis, abnormal genitalia, retardation of growth and deafness. However, hypertrophic cardiomyopathy, the most frequent cause of sudden cardiac death in young people, is the most common cardiovascular manifestation in LS patients and the major determinant of mortality and morbidity. In approximately 85% of the patients with a definite diagnosis of LS, a missense mutation is found in the protein-tyrosine phosphatase non-receptor type 11 (PTPN11) gene located on chromosome 12q24.1. We report the case of an asymptomatic 17-year-old male with a missense mutation (c.836A>G) in exon 7 (Tyr279Cys) of the PTPN11 gene and a non-obstructive asymmetric anteroseptal hypertrophic cardiomyopathy.