While a family tree holds he and his siblings as children of priest Der Avedis Der Avedisian and his wife Bilbil of Mashgerd, Arapkir, Turkey, it is more likely they were his grandchildren. Very little is known about him, except that his wife was named Gadar Ashekian and they had three sons, all of whom were killed in the Armenian Genocide of 1915, and two daughters who both survived and escaped Turkey. The only other fact known about Zakar is that he had the title "Haji Zakar", which means he had made the Christian pilgrimage to Jerusalem. His brother also had the title Haji and it can be assumed they might have gone together, as could be expected of the sons of a priest.

For unknown reasons, it seems many members of the wider Der Avedisian family left Arapkir. It is not known when, but certainly by the late 1890s. Perhaps this was due to the Hamidian Massacres of 1894-1896 during which time Arapkir was attacked and much destruction was done, though this is pure speculation as a family story also mentions that Zakar's son Tateos had moved to the town of Tokat to do business. A family portrait shows one of Tateos's brothers, implying that perhaps he too had moved to Tokat. Zakar's two daughters married men from Arapkir however, which implies that perhaps Zakar and at least part of the family remained there. Descendants of Zakar's brother Haji Artin Agha (Haroutune) moved to the town of Erzincan, sons of his brother Pilbos moved further afield to the coastal city of Zongalduk, and sons of his sister Mariam moved to the capital of Constantinople.

It is unknown when and where Zakar and Gadar died, and whether it was in the Armenian Genocide of 1915 or if they died prior to it.