Extraction methods appear to reduce the potency of disease-causing prions. The risk from gelatin are many times lower than those from the contaminated foods that were consumed at the peak of the BSE epidemic.
Evidence from:
The EFSA Journal (2006) Vol.312 p 1 – 29
“Quantitative assessment of the human and animal BSE risk posed by gelatine with respect to residual BSE risk”
The report concludes that restrictions on the use of brain and vertebrae in the production of gelatine are not justified.
Further detail: