Gene knowledge empowers brokers

01:09, Nov 13 2012

The fast growing field of genetic research is raising questions about whether people should be held less responsible for their actions based on their genes, a legal academic says.

Large studies had shown that the MAO-A gene, combined with an environment where a person was maltreated while young, could mean people were more likely to act out in a violent manner.

If the gene was stronger it could cancel out the environmental factors, Otago University dean and Professor of Law Mark Henaghan said.

"So if that gene is low and there's environmental factors, then there's an argument to be made that those people have a kind of genetic driver which will drive them, combined with the environmental factors, to behave in a way that is more violent," he said.

"So it comes down to the whole issue of responsibility. Should we hold such people equally responsible when they have this physical genetic factor which is going to drive them more closely to behave in certain ways than perhaps others who don't have it? Should we apply the same laws to them?"

On the other hand, there might be an opinion that such people were dangerous and should be locked up for a long period of time.


"So this information can be used in a way that can be quite draconian," Henaghan said.

It was becoming easier and cheaper for people to get genetic information about themselves, the big issue was how to interpret it.

An area where genome sequencing could have an impact was in insurance, with insurers wanting to know as much as they could to minimise their risk.

No specific law covered the issue, and the position now was that insurers would ask someone who had done genetic testing to reveal the results, but people who had not done the testing were not required to do it.

"There's a real issue here of whether or not insurers should require people to have these tests. I don't think they should, but I think if people do have this information insurers should be entitled to take it into account," Henaghan said

"What we really need in place are some protections to make sure that insurers don't overly bias against people who have had such tests."

While there was no legal requirement for people to tell potential employers the results of genetic tests, Henaghan expected strong laws would be needed to prevent discrimination against people found to have certain predispositions to health problems.

There was also no legal requirement for people who found they were predisposed to certain conditions to tell other people who may be in the same position, such as family members.

"The real dilemma is... should you tell someone else if you think that they may have also the same predisposition that you have and they can do something about it."

Normally medical information was confidential between a doctor and a patient, Henaghan said.

"The general feeling is, I think, if it's a general predisposition that something can be done about, which you can by adjustment of lifestyle, or certain treatment, protect your future life it's a good thing to tell other people."

But some people may not want to know if they were highly susceptible to diseases that did not have any cure.

"At the moment there is no legal requirement for people to tell. The only requirement to pass on information is really in situations where someone's in imminent threat of peril." That would not apply with genomic sequencing.

The cost of sequencing a person's genome has dropped rapidly to about $10,000.

Medical scientist Associate Professor Cristin Print, from Auckland University, said genomics was beginning to revolutionise medicine.

Areas where it was having an impact included in making and refining diagnoses or prognoses, personalised treatment and lifestyle prescriptions, testing before birth, and screening.

Digging deeper into the genome had shown that humans were very complex, genomes were not easy to interpret, and that having a particular mutation did not necessarily mean people would get a disease.

"For many mutations or variants in your genome you may or may not get a disease, and whether you do or not depends on luck, your environment, your diet, what infections you had as a child, what exercise you do and so on," Print said.

Large projects sequencing healthy people had found many people had mutations which should disable the function of a gene, but they were disease-free because other genes had been able to take over.

New research had found that in addition to about 30,000 genes a person had there was about another 4m gene switches situated between the genes on the chromosomes, adding "a whole new level of complexity".

"Right now, most clinical genomics, with patients, was done as part of research projects, and we've not quite yet moved into routine use of clinical genomics outside research projects, but it is coming very quickly," Print said.