I just read the wikipedia article more carefully. Her mental retardation before the procedure is highly disputed.

Quote:

She was not mentally retarded. … It could be she had an IQ of 90 in a family where everyone was 130, so it looked like retardation, but she did not fall into IQ 75 and below, which is the definition of mental retardation. … There is no way I can picture her at less than a 90 IQ, but in that family, 90 would be considered retarded."