Gyeltsen Bum (rgyal mthan ‘bum) was born in late fifteenth century in Dege (sde dge). He is counted as the head of the family in its thirty-second generation. His father was Botar Tashi Sengge (o thar bkra shis seng+ge, d.u.), the first king of Dege. He had a monk brother named Pelden Sengge (dpal ldan seng+ge), who was trained at Ngor Ewaṃ Choden (ngor e wa+M chos ldan) in Tsang, under the guidance of numerous masters, includingLhachok Sengge (lha mchog seng+ge,1468-1535), the ninth abbot of Ngor. Pelden Sengge is said to have founded a monastic institution named Nyin Gon (nyin dgon), possibly with the sponsorship of Gyeltsen Bum.
Gyeltsen Bum had four sons. The eldest, Ponchen A-nga (dpon chen A sn
Source: The Treasury of lives