Radioactive elements comprise a majority of the "ACTINIDES"
These are elements in the bottom row of the periodic table.
Its true that the cerebral cortex is the highest portion of the brain.
Two genes, BRCA1, located on chromosome 17q21 (5,6), and BRCA2, located on 13q12-13 (7–9), have been shown to predispose to familial breast cancer.
