Decreased PON1 activity is also observed in patients with type 1 and type 2 diabetic peripheral neuropathy, suggesting that diabetic neuropathy may also arise, in part, due to the increased susceptibility of the nervous system to neurotoxic damage resulting from the lack of protection in diabetics normally afforded by PON1 in non-diabetics [21]. This evidence concerns the gene PON1 and diabetic neuropathy.