Lucknow, Aug 11 - A farmer and his wife in Uttar Pradesh have sought President Pratibha Patil's permission for the mercy killing of all their four sons who have turned into virtual vegetables.

The four, aged 10 to 16 years, have been afflicted by muscular dystrophy, a genetic disease that has confined them to bed.

'My sons cannot stand on their feet. They are unable to move their body below the neck. I see their distress every day. Now when doctors too have lost hope, I want they should die. Death would be the ultimate solution for their suffering,' farmer Jeet Narayan of Bashi village of Mirzapur district, some 300 km from Lucknow, has said in his letter to Patil.

'My sons are in utter discomfort. I cannot see their helplessness any more. So, we have written to the president that our sons be killed through euthanasia,' Narayan's wife Prabhavati told IANS over telephone.