Cancer cells have special adaptation mechanisms that allow them to proliferate despite changes in their genetic makeup.

The new Rangers first baseman announced Friday that he will wear No. 21 to pay tribute ... that is also called Trisomy 21, a reference to a repetition of the 21st chromosome.

ARLINGTON, Texas -- Jake Burger will wear No. 21 with the Texas Rangers ... a condition in which a person is born with an extra chromosome, causing mild to moderate cognitive disability ...