CBS and Cognitive impairment: It is of note, that a performed amino acid quantitative analysis (see Materials and Methods) demonstrated (Figure S3) that, as expected, the deletion of the CBS gene resulted in the accumulation of homocysteine (Hcy) which behaves as a strong excitotoxic neurotransmitter that causes cognitive impairments, vascular dementia, and many other abnormalities in humans and mice [15,17,52].