In the continuing quest to understand Ozzy Osbourne, scientists have finally unravelled the singer's most microscopic mystery: his genes. Following in the footsteps of mice and mammoths, Osbourne had his full genome sequenced and analysed by American researchers, who uncovered mutations related to addiction, metabolism, and Osbourne's Neanderthal ancestors.

"I've always said that at the end of the world there will be roaches, Ozzy and Keith Richards," said Sharon, Osbourne's wife, at a press conference announcing the findings. "He's going to outlive us all. That fascinated me." Reps for a genetics firm called Knome approached the Black Sabbath frontman in 2007, asking if he'd consider joining Harvard professor Henry Louis Gates and DNA co-discoverer James Watson as one of the few human beings to have had their individual genomes sequenced. Osbourne finally consented, giving scientists a blood sample. "I was curious," he explained to the Sunday Times. "Given the swimming pools of booze I've guzzled over the years – not to mention all of the cocaine, morphine, sleeping pills, cough syrup, LSD, Rohypnol … you name it – there's really no plausible medical reason why I should still be alive. Maybe my DNA could say why."

For the moment, the Osbourne genome offers as many questions as answers. "Ozzy carries several hundred thousand variants that have never been seen by scientists," Nathaniel Pearson, Knome's director of research, told Scientific American. "It's going to be a while before we get enough data as a society to understand those variants."

"Many of the variants in his genome are about how the brain processes dopamine," he continued. Osbourne is 2.6 times more likely to experience hallucinations while on marijuana, has an increased risk of cocaine addiction and "an increased predisposition for alcohol dependence of something like six times higher", Pearson said. Osbourne's genes also suggest that he is slow to metabolise coffee. "Ozzy's kryptonite is caffeine," a Knome rep explained. A functioning change to the singer's TTN gene, which has been linked to the nervous system, may be connected to Osbourne's hearing or to his tremors.

"Here's a guy who's rocking heavy metal for decades and he can still hear," said Jorge Conde, Knome's chief executive. "It would be interesting to know if this gene may impact that. [Or] his Parkinsonian tremor – it's hard to know if that is from his genes or from years of hard living."

Furthermore, Osbourne's got a genetic sliver that once belonged to homo sapiens' extinct cousins, the Neanderthals. "For a long time we thought that Neanderthals didn't have any descendents today, but it turns out that Asians and Europeans have some evidence of Neanderthal lineage – like a drop in the bucket," Pearson said. "We found a little segment on Ozzy's chromosome 10 that very likely traces back to a Neanderthal forebear."

"We also looked at [Knome] founder George Church and he has about three times as much [Neanderthal] as Ozzy does," Pearson added. To this, Sharon Osbourne's response was swift: "I'd like to meet him."

Ozzy Osbourne turns 62 next month.