Noonan syndrome with multiple lentigines, previously known as LEOPARD syndrome (LS), is a rare autosomal dominant RASopathy that has many similarities to Noonan syndrome.
On this page:
Clinical presentation
Despite a change in formal name, the 'LEOPARD' acronym is still useful to summarize the clinical features:
L: lentigines (multiple)
E: ECG conduction abnormalities
A: abnormal genitals
R: restriction of growth
D: deafness (sensorineural)
Importantly, this acronym does not include the other craniofacial anomalies (in addition to hypertelorism) which are identical to those of Noonan syndrome and present in nearly all patients 5.
Pathology
Genetics
Thought to result from a mutation in the PTPN11 (protein tyrosinephosphatase nonreceptor type 11) gene located on chromosome 12q24.1 2, which results in increased signaling of the Ras/MAPK pathway. Thus, the disorder is classified as a RASopathy 5.
Associations
Complications
One concerning potential complication is the development of hypertrophic cardiomyopathy (HCM) (often in infancy) related to congenital cardiac defects.
History and etymology
Originally described by R J Gorlin and his colleagues in 1969 1.
Unable to process the form. Check for errors and try again.