Screening of so-called clock genes is looming, enabling us to prove once and for all not only who is an early morning or evening person but also identify those most suitable for shift work, WA sleep medicine expert Jack Philpott says.
Inheriting the recently identified genes that determined an evening person meant a worker was better able to go to sleep after a night shift and then stay asleep for longer.
While those with early-morning clock genes found it more difficult to synchronise their circadian rhythm with their homeostatic drive, the desire to sleep gradually increases the longer you are awake.
Their biological clock may wake them after only a few hours tucked up in bed in a darkened room, making them more prone to on-the-job fatigue.
Initial gene work involved researchers studying thousands of fruit fly colonies, each with a different set of genetic mutations, and analysing their sleep pattern.
"Work is being done in the US in Massachusetts and at Monash University looking at these clock genes and trying to sort out that there are probably some people who should not be working at night because they are more prone to the effects," Dr Philpott, who is based at Hollywood Private Hospital, said. "There is a real reason why more accidents are likely to occur, when the brain is not as reactive as it should be.
"Screening our genes is probably where we are heading.
"But will that be something that society is willing to accept though, in terms of privacy? I am not sure."
Dr Philpott warned such genes could have an effect on road safety and said 4am to 6am was the danger period for sleep-related car accidents.
With an estimated 15 to 17 per cent of the westernised workforce involved in shift work, fatigue management was especially important in shift work and 24-hour occupations such as transport operation, medicine and mining, he said.
Professor David Hillman, of the Australian Sleep Health Foundation, said in Australia at least 9 per cent of serious road crashes were because of fatigue, with 25,920 injuries a year with associated costs of $277,912.00 for each accident.
In the workplace, there were 9584 fatigue-related injuries a year, each costing $131,912.
Green and blue light therapy and melatonin was being used to help some shift workers struggling to synchronise circadian rhythm with homeostatic drive.
The therapy involves a small light box that produces blue light that can adjust sleep patterns, boost mood and increase energy levels.