The ge­netic goldrush

Ge­netic test­ing is cheaper than ever. Com­pa­nies are lin­ing up to sell wine, shoes, fit­ness plans and more – all tai­lored to your DNA. But just how fea­si­ble are their claims?

Focus-Science and Technology - - Contents - Words: Kat Arney

Apps and ser­vices of­fer­ing DNA-based ad­vice on ev­ery­thing from plan­ning a work­out to choos­ing a wine are in­creas­ingly com­mon. Kat Arney finds out more.

n less than two decades, the sci­ence of hu­man ge­nomics – study­ing the ge­netic makeup of in­di­vid­u­als and pop­u­la­tions – has changed be­yond recog­ni­tion. The first full hu­man genome se­quence took 10 years and cost nearly $3bn to de­liver (at 1991 prices). To­day you can spit in a tube, pop it in the post, and ex­pect an email to ar­rive within weeks de­tail­ing thou­sands of vari­a­tions within your DNA linked to traits, health and her­itage, at a frac­tion of the cost.

Un­sur­pris­ingly, en­ter­pris­ing com­pa­nies have been quick to jump on the ge­nomic band­wagon, of­fer­ing ev­ery­thing from fit­ness plans to per­son­alised wine choices based on your genes. But is it re­ally pos­si­ble to get such de­tailed in­for­ma­tion from a glob of your saliva? DI­RECT TO YOUR DOOR The story of di­rect-to- con­sumer (DTC) ge­netic test­ing re­ally starts in the early 2000s. At this time, rel­a­tively lit­tle was known about how small dif­fer­ences in DNA se­quences be­tween peo­ple – known as sin­gle nu­cleo­tide poly­mor­phisms, or SNPs (pro­nounced ‘snips’) – mapped on to dis­ease risk or phys­i­cal traits such as height, weight or taste pref­er­ences.

Nonethe­less, com­pa­nies sprang up of­fer­ing pricey nu­tri­tional ad­vice and sup­ple­ments based on test­ing a hand­ful of SNPs. Given the lack of solid sci­en­tific ev­i­dence link­ing SNPs to char­ac­ter­is­tics, these were dis­missed by the au­thor­i­ties as be­ing med­i­cally un­proven and am­bigu­ous.

By the mid­dle of the decade, the genetesters had started to wise up. Rather than pur­port­ing to of­fer any kind of med­i­cal ad­vice or di­ag­no­sis, which would lead them to fall foul of reg­u­la­tors such as the US Food and Drug Ad­min­is­tra­tion (FDA), they now claimed to pro­vide their SNP tests purely for in­for­ma­tional and ed­u­ca­tional use. By 2009, more than 500 SNPs had been re­li­ably linked to the risk of dis­eases such as cancer, and this

was grow­ing year- on-year. Any­one with a burn­ing bi­o­log­i­cal cu­rios­ity and a thou­sand dol­lars to spare could now sign up to ‘get their genomes done’. Yet de­spite their grow­ing pop­u­lar­ity, when ex­perts an­a­lysed the re­sults of these tests they found them to be mis­lead­ing or even just plain wrong, driven by de­cep­tive mar­ket­ing rather than sound sci­ence.

Put off by reg­u­la­tory crack­downs and a lim­ited con­sumer base, many of the orig­i­nal SNP-based per­son­alised genetics firms closed down or sold out to larger firms. But there have been a few sur­vivors, and these com­pa­nies con­tinue to link SNPs to a wide range of dis­ease risks, phys­i­cal traits and an­ces­try. And as the pace of tech­nol­ogy has ac­cel­er­ated and costs have plum­meted, the ge­netic mar­ket­place is open­ing up once again.

FAM­ILY TIES

One of the big boom ar­eas is in ge­netic an­ces­try ser­vices, with com­pa­nies of­fer­ing to find your lon­glost ge­netic rel­a­tives and trace your roots around the globe. Some of them even tell ro­man­tic sto­ries of an­cient tribes, fierce bar­bar­ians or so­phis­ti­cated

“THERE’S VERY LIT­TLE HARD EV­I­DENCE THAT A GE­NET­I­CALLY-TAI­LORED DIET IS ANY MORE EF­FEC­TIVE THAN A GENERIC ONE”

artists lurk­ing up the an­ces­tral fam­ily tree.

It’s cer­tainly pos­si­ble to pin ge­netic her­itage to cer­tain parts of the world, par­tic­u­larly for pop­u­la­tions rather than in­di­vid­u­als (though even then it’s a rel­a­tively im­pre­cise sci­ence), as well as fig­ur­ing out what per­cent­age of your genome came from Ne­an­derthals. But many sci­en­tists work­ing in the field of hu­man genetics and evo­lu­tion are less con­vinced. For ex­am­ple, re­searchers from the Molec­u­lar and Cul­tural Evo­lu­tion Lab­o­ra­tory at Univer­sity Col­lege Lon­don have in­ves­ti­gated and de­bunked the more du­bi­ous claims as lit­tle more than “ge­netic astrol­ogy”. They ar­gue that the com­plex pat­terns of hu­man mat­ing and mi­gra­tion make it tricky to tease apart the tan­gled ge­netic threads in each of us with any de­gree of ac­cu­racy.

The other hot topic in DTC test­ing comes un­der the broad ban­ner of ‘life­style’. Com­pa­nies now of­fer the chance to ‘hack your body’ and ‘boost your hu­man po­ten­tial’ with all kinds of di­etary and fit­ness ad­vice tai­lored to your per­sonal com­bi­na­tion of cer­tain SNPs. Some rec­om­mend com­bi­na­tions of ‘ge­net­i­cally se­lected’ vi­ta­mins and di­etary sup­ple­ments, while oth­ers even of­fer per­son­alised meals de­liv­ered di­rect to your door. But although these tests all claim to be sup­ported by sci­ence – and while it’s true that the SNPs they test for have been linked to weight, me­tab­o­lism or other phys­i­cal traits in large stud­ies – there’s ac­tu­ally not very much hard ev­i­dence avail­able to sug­gest that fol­low­ing a ge­net­i­cally-tai­lored diet and fit­ness plan is more ef­fec­tive than fol­low­ing a generic one.

In fact, a large ran­domised con­trolled trial car­ried out by sci­en­tists at Univer­sity Col­lege Lon­don and pub­lished in 2015 showed that giv­ing peo­ple a weight loss pro­gramme along­side in­for­ma­tion about their per­sonal ver­sion of a gene called FTO – which is as­so­ci­ated with body weight – made them more likely to think about los­ing weight, but wasn’t any more ef­fec­tive than the pro­gramme alone.

An­other study showed no change in be­hav­iour, at least in the short term, for peo­ple who were given ge­netic in­for­ma­tion about their risk of type 2 di­a­betes – although on the plus side, there was no in­crease in worry or anx­i­ety either.

“My feel­ing is that [DTC tests use] quite a clever mar­ket­ing strat­egy,” says Dr Caro­line Wright, pro­gramme man­ager for the UK’s De­ci­pher­ing De­vel­op­men­tal Dis­or­ders study and sci­en­tific lead at Ge­nomics Eng­land. “I think the sci­ence be­hind some of these things is go­ing to be ten­u­ous. There are re­search pa­pers that link vari­a­tions in DNA with cer­tain at­tributes, but it doesn’t nec­es­sar­ily mean that if you test that par­tic­u­lar vari­ant in a par­tic­u­lar per­son it will be pre­dic­tive for what they like or what they can do.”

MORE DATA, MORE PROB­LEMS

Tak­ing ad­van­tage of the ever-shrink­ing cost of DNA se­quenc­ing, DTC com­pa­nies are now mov­ing on from SNPs and tak­ing a deeper look at the hu­man genome. The next step is ex­ome se­quenc­ing – read­ing the en­tire ge­netic recipe of all 20,000 genes in the genome, with­out the mis­lead­ingly named ‘junk’ DNA that lies in-be­tween.

The first firm into the ex­ome mar­ket­place is Helix, backed by DNA tech­nol­ogy gi­ant Il­lu­mina. Based on the prin­ci­ple of ‘se­quence once, query of­ten’, Helix plans to store cus­tomers’ ex­ome data and al­low them to ac­cess it through an app store, with third-party part­ners of­fer­ing gene-matched prod­ucts rang­ing from health anal­y­sis to life­style ad­vice.

The first prod­uct on of­fer is Geno 2.0, which is an an­ces­try anal­y­sis pack­age that’s pro­duced in as­so­ci­a­tion with Na­tional Ge­o­graphic. Fur­ther part­ners are in the process of sign­ing up, in­clud­ing a range of aca­demic in­sti­tu­tions such as Duke Univer­sity and the Mayo Clinic. On the less se­ri­ous side is Vi­nome, which of­fers cus­tomers reg­u­lar de­liv­er­ies of ge­net­i­cally-matched fine wines with “a lit­tle sci­ence and a lot of fun”.

Whether Helix’s ex­ome-and-app ap­proach of­fers any­thing more than the SNP-based an­ces­try or diet and well­ness tests re­mains to be seen. The thornier is­sue will come if Helix of­fers anal­y­sis of genes in­volved in dis­ease. Not only does this skirt the line with reg­u­la­tory agen­cies such as the FDA, which de­mands that med­i­cal tests are only avail­able

2 through a doc­tor, but it raises im­por­tant sci­en­tific is­sues too.

“There is no doubt that there is a small but im­por­tant per­cent­age of peo­ple who could hugely ben­e­fit from ex­ome se­quenc­ing, by dis­cov­er­ing that they have a spe­cific ge­netic vari­ant that causes a dis­ease,” ex­plains Wright. “But we know that ev­ery­body’s genomes are in­cred­i­bly vari­able.”

She points out that while we have ro­bust in­for­ma­tion on com­mon SNPs that are linked to dis­ease risk, open­ing this up to whole ex­omes is a huge leap into the un­known. Most peo­ple have at least some rare or unique ge­netic vari­a­tions that look like they ought to be harm­ful, yet are com­pletely healthy (see the cover fea­ture of BBC

Fo­cus, Septem­ber 2016). The big chal­lenge is work­ing out how all the tweaks and changes in some­one’s genome work to­gether to in­flu­ence their health.

“We don’t have a huge amount of data, and the po­ten­tial for over­diag­no­sis and telling some­one they have a ge­netic pre­dis­po­si­tion [to­wards a cer­tain dis­ease] is go­ing to be quite tempt­ing,” says Wright. “You can tell a story around pretty much any­one’s ex­ome, and ev­ery­one will have po­ten­tially in­ter­est­ing-look­ing vari­ants. Some of these will gen­uinely cause dis­ease, but many will not.”

Helix de­clined to speak to us, say­ing that their ser­vice will only launch in the US in 2017, and that there are no im­mi­nent plans to bring it to the UK.

But with the cost of se­quenc­ing falling rapidly, it might only be a mat­ter of time – es­pe­cially as Il­lu­mina’s new No­vaSeq ma­chine prom­ises to bring the $100 genome within range. Yet for all the ex­cite­ment and talk of high-tech apps fu­elling the con­sumer ge­nomic rev­o­lu­tion, the same is­sues re­main that have al­ways dogged ge­netic test­ing, par­tic­u­larly around pri­vacy, con­sent and the ques­tion of who gets ac­cess to the data.

Yet for all the ex­cite­ment and talk of high-tech apps fu­elling the con­sumer ge­nomic rev­o­lu­tion, the same is­sues that have al­ways dogged ge­netic test­ing re­main, par­tic­u­larly around pri­vacy, con­sent and the ques­tion of who gets ac­cess to the data. Whiling away some idle time in a ge­netic app store is likely to be a harm­less cu­rios­ity for most peo­ple, and at a time when it’s im­por­tant to en­cour­age the pub­lic to en­gage with genetics, it seems churl­ish to raise a note of cau­tion. But wring­ing data out of your genome could raise more ques­tions than it an­swers.

“THE SAME IS­SUES THAT HAVE AL­WAYS DOGGED GE­NETIC TEST­ING RE­MAIN, PAR­TIC­U­LARLY AROUND PRI­VACY AND CON­SENT”

“In­for­ma­tion about an­ces­try, fit­ness and what kind of wine you like might also be mixed in with whether you’ve got high sus­cep­ti­bil­ity to breast cancer or a gene vari­ant that means you’re go­ing to get Alzheimer’s dis­ease early in life,” says Wright. “Those are quite dif­fer­ent types of in­for­ma­tion, but you’ll be able to get it all from your genome. Some of them are fun, and some of them re­ally aren’t.” We’re see­ing the start of a ge­nomic gold rush: in a few years, hav­ing your DNA se­quenced and ri­fling through it could be as sim­ple and fun as brows­ing TV box sets. But it’s im­por­tant to re­mem­ber that these com­pa­nies hook cu­ri­ous con­sumers with prom­ises of ge­netic in­sights be­cause they want to make money. This is pow­er­ful, per­sonal in­for­ma­tion, with po­ten­tially life- chang­ing con­se­quences, and it’s worth han­dling with care.

BE­LOW: A printed copy of the hu­man genome fills a whole book

RIGHT: A chip con­tain­ing DNA is loaded into a ma­chine for anal­y­sis

ABOVE LEFT: An au­tora­dio­gram show­ing the or­der of nu­cleo­tide bases in a sam­ple of DNA

ABOVE: A DNA se­quence re­veals the pres­ence of APO E, a ge­netic marker for Alzheimer’s

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