donated genome testing raises hopes for better treatment for autism

by: kevin griffin

fifteen-year-old nickolas johnston is one of 100 youngsters chosen to have their entire genetic codes mapped in an effort to develop more targeted treatments for autism.nickolas, his mom tanya and dad greg are all waiting for the results that are expected in about six months.tanya johnston said doctors thought her son would really benefit from being included in the 100 kids.“i wanted to enrol nickolas in the testing immediately because it can be a lifesaver in terms of not only how to treat him in future and what to expect, and most importantly, how to work with him in everyday life,” she said. “the more you can find out genetically the better off they are in the hopes of living a full and healthy life.”the 100 tests have been donated to the pacific autism family network by illumina canada. a genome test creates a record of a person’s dna. in humans, the genome contains more than three billion dna base pairs. the donation is the equivalent of $198,000.johnston said her son, adopted at birth, lives with autism spectrum disorder and behaviours diagnosed as pervasive developmental disorder not otherwise specified. like all cases of autism, the disorder manifests itself uniquely in each person.and that’s why johnston believes the results of the genome test may benefit her son. what it can do is identify particular genetic markers that can point to specific treatments.“in some cases, a particular probiotic can help kids in their emotional regulation because the genome testing shows they’re missing something,” she said. “yes, they still have autism, but they don’t have such a difficult time expressing themselves or showing their emotions.”dr. suzanne lewis is pacific autism’s chief medical officer and vice-president of research. she describes genome testing as “changing the current paradigm of how autism is diagnosed and treated.”“i think it has been life changing in some cases,” she said. “i’m not trying to slam the current approach because it’s been very valuable. you can’t do the behaviour approach and diagnostic approach alone. it has to go hand-in-hand with medical and biological studies to underscore what we’re treating.”she said some behaviour therapies for autism don’t work but no one knows why that’s the case.but genome testing that shows genetic markers of autism can result in new therapies and treatments that target causes rather than symptoms, she said.lewis told the story of one child with autism who had a similar kind of genetic testing called an exome that maps a much smaller part of a person’s dna. but the test was still able to identify the underlying genetic reason for the child’s behaviour, which was treated with medication.“it made an incredible difference for that child,” she said. “so it’s going from the current situation where it’s largely behaviour interventions to move to sequencing and identifying underlying causes or biological factors that are potentially treatable.”the cost of a whole genome test per person is about $6,500.illumina canada is part of illumina, a u.s. multinational biotech company headquartered in san diego. it has been called the “google of genetic testing” by wired.lewis said current research has identified more than 131 gene variants linked to autism.“autism … is highly variable in each individual because it is due to many different causes,” she said. “it is not necessarily as simple as a single gene but genes that might work with other pathways that affect how the brain functions.”illumina canada provided the 100 genome tests, she said, to show public-funding bodies that diagnostic testing shouldn’t be limited to the most severe cases of autism.“this should be a core part of the diagnostic process of autism,” she said.lewis said it’s a good question about who owns the information once a person’s genome is decoded.“the sequencing is owned by the patients in my opinion,” she said.lewis is in the department of medical genetics at the b.c. children’s hospital & women’s health centre, which is funded by the provincial health services authority.the authority, she said, will fund some exome testing but only if the request is in writing. in many cases funding has been turned down because the authority doesn’t think it will help treating a child with autism.genome testing isn’t covered by the authority at all, lewis said.meribeth burton, ministry of health spokesperson, said the only determinant for genome or exome testing is medical need.“b.c. health professionals can apply, on behalf of their patients, for genome or exome testing on a case by case basis,” she said by email.“phsa does not fund whole genome and whole exome sequencing for children diagnosed with non-syndromic autism in bc.“phsa is working closely with the ministry to develop evidence-based clinical guidelines on genetic and genomic testing within a precision medicine policy framework for the province.”pacific autism is holding its big fundraiser nov. 29 at the jw marriott hotel parq. about 1,000 people are expected to attend. tickets are available at $250 each, with the net proceeds going to the group.kevingriffin@postmedia.com