Alexander Tomkin was born on 21 July 1936, the first son of Harris Tomkin, ophthalmic surgeon and his wife Sarah née Nelson. He attended Castle Park Dalkey, St Columba's College, Tathfarnham, and Trinity College, Dublin, where he took the Nurock Prize for classics and the silver medal of the Biological Society. In 1960 he received both the Haughton Prize for medicine and for surgery. After house appointments at Sir Patrick Dun's Hospital, he demonstrated anatomy at Trinity and then spent some years working at Moorfields, in London. His final appointment was as consultant in ophthalmic surgery at the Royal Victoria Eye and Ear Hospital, Dr Steevens', the Rotunda and Sir Patrick Dun's Hospitals in the city of Dublin. He enjoyed music and playing tennis. He married in 1972 but the name of his wife is not known. He was only 48 years old when a friend, Mervyn Taylor TD, notified the College of his death which was probably in April or May 1984.