People with paternal UPD for chromosome 15 have two copies of the UBE3A gene, but they are both inherited from the father and are therefore inactive in the brain.
As persoas con UPD no cromosoma 15 teñen dúas copias do xene UBE3A, pero ambas as dúas foron herdadas do pai e son, por tanto, inactivas no cerebro.