Meanwhile, Ryan was fighting for visiting rights in the Auckland Family Court, which he won on an interim basis.
During that battle, a Family Court judge picked up on the illegal DNA activity and reported the woman to police.
Late last year, Waitakere District Court Judge Simon Maude requested new DNA samples which proved Ryan was the boy's biological father.
But, hours after the judge's order, police allege the mother asked DNA Diagnostics to destroy her and her son's samples.
Ryan, 37, told the Herald on Sunday he had been living a nightmare without his son.
"He hasn't had his father. Boys need their dad, they need their mum too, they need both parents ... it has broken my heart," Ryan said.
He said his former partner became pregnant within three weeks of their getting together and the relationship turned sour because "I didn't love her".
He claimed his ex-partner falsely accused him of being a rapist, a drug addict, a gang member and a stalker following the break-up.
"The hell she has put me through - I wasn't asking for much, I wasn't asking for custody. I just wanted to see him and let him know me. It is his right to know his father. My life has been on hold."
Ryan, who has two children from a previous marriage, said the last time he saw his son was almost two years ago.
"It was raining so we were locked inside, just playing with his toys, piggy-back rides, it was such a good day.
"I think about [him] every day. I just hope he forgives me," Ryan said.
His ex-partner said she could not comment during court proceedings but had a "good story" to tell. She will be sentenced in court in June.