Darold Treffert in Scientific American:
Leslie Lemke is a musical virtuoso even though he has never had a music lesson in his life. Like “Blind Tom” Wiggins a century before him, his musical genius erupted so early and spontaneously as an infant that it could not possibly have been learned. It came ‘factory installed’. In both cases professional musicians witnessed and confirmed that Lemke and Wiggins somehow, even in the absence of formal training, had innate access to what can be called “the rules” or vast syntax of music.
Alonzo Clemons has never had an art lesson in his life. As an infant, after a head injury, he began to sculpt with whatever was handy–Crisco or whatever–and now is a celebrated sculptor who can mold a perfect specimen of any animal with clay in an hour or less after only a single glance at the animal itself–every muscle and tendon perfectly positioned. He has had no formal training.
To explain the savant, who has innate access to the vast syntax and rules of art, mathematics, music and even language, in the absence of any formal training and in the presence of major disability, “genetic memory,” it seems to me, must exist along with the more commonly recognized cognitive/semantic and procedural/habit memory circuits.
Genetic memory, simply put, is complex abilities and actual sophisticated knowledge inherited along with other more typical and commonly accepted physical and behavioral characteristics.
More here.