WAYNE O'Donoghue has vehemently denied that a tiny trace of semen found on Robert Holohan's body belonged to him.

In an exclusive interview at Midlands Prison, the first time he has spoken publicly since he killed 11-year-old Robert, O'Donoghue said: "I am not a paedophile. That semen was definitely not mine, and I couldn't believe when people started to say that there was anything going on between us."

A previously undisclosed report, carried out by a leading British forensic science laboratory, corroborates O'Donoghue's insistence that nothing improper took place between himself and Robert Holohan.

In a new development, the Sunday Tribune has obtained the report carried out by Hayward Associates, a Cambridge-based forensic science laboratory.

"In my opinion, the scientific findings do not provide any support for the view that any sexual acts took place between Wayne O'Donoghue and Robert Holohan, " stated Emma Lynch, a consulting forensic scientist.

O'Donoghue has always contended that the tiny trace of semen found on Holohan's right hand was innocently transferred from the bath mat to Holohan's hand when O'Donoghue placed him there while trying to revive him.

Lynch states in an intricately detailed report that "it is possible that semen was transferred to Robert Holohan's hands and nails indirectly, for example, as a result of him having been placed on the semi-stained bath mat."

O'Donoghue's father Ray and his two brothers submitted swabs to the UK laboratory.

Lynch's report reveals that the semen on the bath mat matches one of them.

O'Donoghue described his shock at allegations levelled at him by Robert Holohan's mother Majella in her victim impact statement made at his sentencing hearing in January.

"I have no problem doing my time in here, but there is no way there was anything going on between Robert and myself, " the 21-year-old said.

"I cannot say how sorry I am for everything that happened to them. I will feel sorry for what I did until the day I die."

O'Donoghue said, "I never stop thinking about what happened. I think about it 24-7.

"I think about the Holohan family a lot, as they have lost Robert out of all this."