Dos hermanos con síndrome de Prader-Willy por deleción clásica. ¿Es la excepción que confirma la regla?

An Update on Molecular Diagnostic Testing of Human Imprinting Disorders

“…For cases with inherited mutations or genomic alterations, prenatal diagnosis should be offered as recurrence risk is high, that is, 50% for the majority of IDs and 25% for TNDM1 caused by ZFP57 mutation. In cases with de novo mutations or genomic alterations, the recurrence risk is low; however, the possibility of germline mosaicism exists, 55,56 thus, prenatal testing could be offered for reassurance. UPD with normal karyotype is considered a sporadic event and invasive prenatal testing is not indicated.…”