(a) Several green leafy vegetables (e.g. Amaranthus, spinach etc.) being rich in oxalate, if ingested in large quantity are toxic, since oxalate chelates calcium and also destroys renal tissues in kidney.

(b) The attack and spread of a fungns (Whetzeliniasclerot iorium), which causes damage to crops like sunflower involves accumulation of oxalic acid in the infested tissue.

(c) Oxalic acid is an essential substrate for the synthesis of the neurotoxin called, β-N-oxalyl I-L-α, β diaminopropionic acid (ODAP), found in different parts of the plants of Lathyrus sativus (khesari dal).

Consumption of this legume causes neurolathyrism, a well known disease causing damage to leg muscles, etc. ODAP interferes with metabolism of glutamic acid, which is involved in transmission of nerve impulses in the brain, so that despite its rich protein content, L. sativus can not be used as a food source.

In all the above cases (leafy vegetables, sunflower & L. Sativus), transfer of single gene for oxalate decarboxylase to produce transgenic plants will improve these plant species by reducing the oxalate content.

This new gene will also allow the development of a diagnostic kit to measure oxalate in blood and urine, since prevalent methods for clinical tests are quite expensive.