Sentence:  This amazing occurrence made my head go bong to say the least; it was obvious that Elizabeth had not been “schizophrenic” because of her <WSD>genetics</WSD>, nor because of stress, nor malnutrition, nor hypoglycemia, nor because of any of the causes of mental illness that I had learned and rectify, but because of food allergies 
Meaning of the word marked with <WSD> tags:  The genetic makeup of a specific individual or species.