yes alot of gelatin is made off grinded up pig bones and tissue
and eating this can still cause you to get sick -
Gelatin (US spelling) or gelatine (British spelling) (used to make Jell-o and other desserts) is made from the boiled bones, skins and tendons of animals.
An alternative substance is called Agar-Agar, which is derived from seaweed.
Another is made from the root of the Kuzu. Agar-Agar is sold in noodle-like strands, in powdered form, or in long blocks, and is usually white-ish in color.
http://www.ivu.org/faq/gelatine.html