14 FT.COM/MAGAZINE MARCH7/
◀childreninherit edtwomutatedgenes, andtheir
redblood cells collapsedinto cr escents ,clogging
their blood vessels.The result is whatwenow call
sickle cell anaemia–apainful, sometimesdeadly
geneticdisorderthatafflicts300,000babiesevery
year,mostlyinAfrica.
Thelinkbetweensicklecellandmalariawas
establishedinthe1950sandhadaprofoundimpact
on the field of human molecular genetics.But the
existence of the child–which maybec rucial in
findingacure–was not discovere duntil 2018,by
CharlesRotim iandhiscolleagueDanielShrinerat
theUS NationalInstitutesofH ealth.
The mapping of the entirehuman genome –
a13-year effort to list all of theroughly3billion
“letters”thatmakeupaperson’s DNA–wascom-
pletedin 2003.Since then, thereference genome
that scientists use to conducttheir research has
steadilygrown, adding different types of people
to further our understanding of the fundamen-
tal building blocks of human life. But itremains
incomplete: nearly20years on, thevast major-
ityofitiss till European.Genetic material from
peopleofAfricandescentmakesupjus t2percent.
It was this smallportion that producedRotimi’s
groundbreakingresearch.
ThelackofAfricangeneticmaterialconstitutes
asignificant obstacle to understanding howour
bodiesand diseasesfunction. African genomes
arenot onlyhumanity’soldestbut our most
diverse, and that diversityholds within it an
almost unfathomablepotential–fromscientific
breakthroughs to geneediting to therewriting
of ourevolutionary history,the very storywe tell
ourselvesaboutourselves.
“ThecontinentofAfricarepresentswhatIwould
liketocalltherootandtrunkofhumanevolution-
ary history,” Rotimi tells meoverthe phone from
Maryland,whereheisthedir ectoroftheCenterfor
Research onGenomics and Global Health at NIH.
“WehavelivedthelongestashumansontheAfri-
can continent, and that hasvery,veryimportant
implications for understanding... howforce sthat
existedonthecontinenthelp edshapepresent-day
humangenomes,eitherintermsofhowtos urvive
infectiousdiseasesorsurvivetheenvironment.”
Researchers,academics,drug companiesand
start-ups around theworld ha ve re centlywoken
uptothepotentialthatAfricaoffers.Aconsortium
of roughly500 African scientists is conducting
groundbreakingresearch on the genetic causesof
blindness, Alzheimer’s, cancer,kidneydiseaseand
otherafflictionsundertheumbrellaoftheH3Africa
programme–ani nitiative create dbyRotimi, and
funde dbyt heNIHandtheUK’sWellcomeTrust,in- Theirwork,Rotimi says,isj ustbeginningto
bear fruit.Meanwhile,pharmaceutical groups are
onth ehuntforgenomicdatafromAfricanpopula-
tions–ins omecasesprovidedbyn ewhome-grown
biotechstart-ups–ast heyseektod evelopthenext
generationofblockbustergene-basedtherapies.
Ther eis, however, concern about who will ulti-
matelyownAfrica ’s genomicdata.AUS officialtold
theFTl astmonththat the Trumpadministration
wantedtob lock China’s plans to build an $80m
headquarters for the AfricaCentres for Disease
Control and Prevention, in large partbecauseof
Africa ’s “vastamountsofgenomicdata”. “TheChi-
nese ...wanttoeventuallystealthedata,”theofficial
said(Beijingcalledtheallegation“ridiculous”).
As the commercialpossibilities become clear,
and private companiesfromthe US ,Europ eand
China take an inter est, scientists in Africa are
grapplingwiththecomplexethicalimplicationsof
practisinganextracti vescienceonacontinentwith
alonghistoryofexploitationfromabroad.
Roughly99percentofourevolutionaryhistory
occurr edinAfrica.Modernhumansemergedthere
200,000 years ago.About 100,000 years later,
small groups of our collectiveancestorsbegan
aprocreational march around theworld. They
tookwiththemjustafractio nofo urgeneticdiver-
sity.ThoseinAfricaheldthevastmajority,andas
theyintermarried and reproduced, that diversity
remained,buffeted andtransformedbye nviron-
mentalpressu resincludingdisease.Tapping into
thatdiversityhasimplicationsforallofhumanity.Notlongago,atailor cametomyhomeinLagos
totak emymeasurements.Iaskedhimifhecould
also makedressesfor my daughters.Hes aid he
knew someone who could, hisex-business part-
ner.Actually, hesaid,shewasalsohisex.Ah,Isaid,
it’salways hardtom ixbusinessandlove.No,no,it’s
notthat,hesaid.We’rebothAS.
Inside each human cell isanucleus with about
20,000genesmadeupofstrandsofDNAthatcon-
tainfour chemicals callednucleotides, or bases.
Theentirehumangenome–whichincludesallofa
person’s genes –contains3.2billion pairs of those
bases–lettered A, C, Tand G–which provide the
blueprintforho wourcellsfunction.
Twocopiesofthe haemoglobin gene sit in each
of those cells.For some Africans,one of them is
normal (A) and one of them is mutated(S). They
carr ythe sickle cell trait but don’t suffer from the
disease.Roughlyaquarter of Nigerians areAS;
the country accounts for half of the babiesborn
with the disease eachyear.When thingsbetween
thetailorandhisgirlfriendgotserious,they–like
mostyoungNigerians–tookagenetictest .Hew as
unlucky, as many others across Africa and in the
diaspora are, to have fallen in love with another
descendant of thechild born in the GreenSahara,
hundredsofgenerationsdowntheline.
Genomicresearch is thesearchfor variation.
Humansshareroughl y99.9percentoftheirDNA
but it is the difference in whatremains that is
important.These mutations areknown as SNPs,
orsingle-nucleotidepolym orphisms–theequiva-
lentofasingl etypoina llofthewordsinathousand
bibles. Most ar ebenign, causing blueeyes or big
ears or nothing at all.The onesscientists seek are
moredangerous–causing cancer,Alzheimer’s,
high cholesterol, Parkinson’s –and moreheroic,
prote ctingusfromsuchafflictions.
Withoutincluding the genetic data ofAfricans,
precision medicine, geneeditingand other
scientific advances risk becoming theprovince
of the white andwealthy.Many genetic tests are
alreadybetter at predicting breast cancer and
type-1diabetesinp atients of European descent
thanclinicalmethods,becausethetestsarebased
onthem.Thisbiasis“themostcriticallimitationto
geneticsinprecisionmedicine”,accordingtoa
paperinthejournalNatureGenetics.
Broadeninggeneticresearchwillbenefitevery-
one.Yearsago,DrO lufunmilayo Olopade ,one of
America’sleadingcancerresearchers,begannotic-
ing higher ratesofb reast cancer,ate arlier ages,▶OMANSETHAHOUANSOUFT.COM/MAGAZINE MARCH7/82020 15‘Ithinkit’smoreacceptabletotheAfricanpo pulation ifthey
seetheirpeersdoingtheresearch,ratherthanseeingpeople
fromoutside. Thatcanremindpeopleoftheolddays,of
peoplecominginandtakingtheresourcesandgoingout’
GuidaLandouré,Bamako,Mali