I've been in search of my deceased father's biological family. He was placed for a closed adoption 60+ years ago. I've discovered the two families who parented him thanks to Ancestry DNA matches. We've been able to narrow it down further on one side to a woman who I thought likely mothered him. Her past and looks fit perfectly down to the year she placed a baby for adoption.
This woman's biological son took a DNA test to confirm our relationship. He's only showing up as a 519 centimorgan match across 25 segments. This is matching at about the same level as my father's 1st cousins (my first cousins once removed). Is there still a chance he's my half uncle at these levels or a way we can confirm our relationship further?
I'm female and an only child. Based on the results, I'm leaning towards him actually being a 1st cousin to my late dad but the coincidences of his mother's past are uncanny. The chart levels I've been referencing show the half uncle/niece relationship falling between 540-1175cm, so we are just under that.
For further reference here: This man has another confirmed half brother from a different side (unrelated to my side) and he's only matching 1272cms to him which was at the low level of half siblings. Chart levels for half siblings are usually between 1320-2100cm. Perhaps this man is at the low level with his half brother and me??
Two of my other close matches for first cousins once removed, from the same family, are showing at 422cm across 16 segments and 416cm across 21 segments. I have one other first cousin once removed from the other side of my father's family coming in at a slightly higher level of 565cm across 25 segments.
I've done a 23 and Me test but he has not. This is all strictly from Ancestry results.