HUMAN GENETIC ADAPTATION TO HIGH ALTITUDE · • Compare differences between two isolated populations ... -Similarities between development of EPA and of some mitochondrial diseases

HUMAN GENETIC ADAPTATION TO HUMAN GENETIC ADAPTATION TO HIGH ALTITUDEHIGH ALTITUDE

Catherine Godinot

PhysiologicalPhysiological adaptation versus adaptation versus geneticgenetic selectionselection

• Aclimatization : – Immediate– Days– Years

• Development– Before birth, during growth

• Genetic selection Over many generations :– Increased fecondity, improved or decreased survival during

embryogenesis and after birth– Resistance to diseases– Gene polymorphism selection

• Relations Polymorphisms !" Adaptation to HA

BirthBirth weightweight andand Adaptation to AltitudeAdaptation to Altitude

From Moore L (2004) Placenta Supplement A Trophobalst research, 18, S60-S71




• Genetic selection Over many generations :– Increased fecondity, improved or decreased survival during embryogenesis and

after birth

– Resistance to diseases

– Gene polymorphism selection


Factors involved in oxygen availability Factors involved in oxygen availability to tissues implying many genesto tissues implying many genes

O2 in atmosphereOXYGEN TRANSPORT LUNG PUMPING

Lung alveolesARTERIAL OXYGEN CONTENT HEMOGLOBIN CONTENT

and AFFINITY TO OXYGENArterial Blood

REGIONAL BLOOD FLOW HEART PUMPINGWhole body capillaries

ORGAN BLOOD FLOW VASCULAR NETWORKTissue, Permeability

Proteins binding and metabolizing oxygenMETABOLISM

MitochondriaDensity and Distribution

Activities of enzymes using oxygen: cytochrome oxidase and Reactive Oxygen Species

Possible Genetic Adaptation of Possible Genetic Adaptation of High Altitude Andean populationsHigh Altitude Andean populations

From Rupert and From Rupert and HochachkaHochachka (2001) High altitude (2001) High altitude MedecineMedecine and Biology, 2, 235and Biology, 2, 235--256) 256)




• Genetic selection Over many generations :– Increased fecondity, improved or decreased survival during embryogenesis and

after birth

– Resistance to diseases

– Gene polymorphism selection


NitricNitric oxideoxide synthasesynthase

Exhaled NO (ppb)Exhaled NO (ppb)TibetansTibetans AndeansAndeans LowLow--landerslanders(4,200 m)(4,200 m) (3,900 m)(3,900 m) (USA)(USA)

StandardStandard 18.6 18.6 9.59.5 7.47.4(n)(n) (105)(105) (144)(144) (33)(33)

p<0.001p<0.001 p<0.01p<0.01

After oxygenAfter oxygen 21.121.1 9.69.6InspirationInspiration (26)(26) (25)(25)(42(42--50 %)50 %) p<0.05p<0.05 p>0.05p>0.05

-- NO drops for lowlanders upon acute exposure to low oxygenNO drops for lowlanders upon acute exposure to low oxygen-- However, exhaled NO is higher in Tibetans and Andeans in spite However, exhaled NO is higher in Tibetans and Andeans in spite of their of their higher hemoglobin contentshigher hemoglobin contents-- Oxygen inspiration increased exhaled NO in Tibetans but not in Oxygen inspiration increased exhaled NO in Tibetans but not in Andeans Andeans suggesting different mechanisms and genetic influencesuggesting different mechanisms and genetic influence-- Functional advantage of High NO: enhanced oxygen uptake in lungFunctional advantage of High NO: enhanced oxygen uptake in lungs, s, hence improving oxygen delivery to tissueshence improving oxygen delivery to tissues

Adapted from Beall et al (2001) Nature, 414, 411-412

Factors involved in oxygen availability Factors involved in oxygen availability to tissues implying many genesto tissues implying many genes

O2 in atmosphereOXYGEN TRANSPORT LUNG PUMPING

Lung alveolesARTERIAL OXYGEN CONTENT HEMOGLOBIN CONTENT

and AFFINITY TO OXYGENArterial Blood

REGIONAL BLOOD FLOW HEART PUMPINGWhole body capillaries

ORGAN BLOOD FLOW VASCULAR NETWORKTissue, Permeability

Proteins binding and metabolizing oxygenMETABOLISM

MitochondriaDensity and Distribution

Activities of enzymes using oxygen: cytochrome oxidase and Reactive Oxygen Species

ADP + Pi --> ATP

Historical, Archeological, linguistic, Historical, Archeological, linguistic, geographic influence on Genetic driftgeographic influence on Genetic drift

•• Time of residence in HA and specific genetic adaptations:Time of residence in HA and specific genetic adaptations:Tibetans >Andeans >Europeans >HanTibetans >Andeans >Europeans >Han--Chinese > Chinese >

EthiopiansEthiopians•• Genetic driftGenetic drift

–– Loss of genetic variation due to low population size: Loss of genetic variation due to low population size: founder effectfounder effect

–– Gene flow: introduction of new genes by admixture Gene flow: introduction of new genes by admixture inbreeding inbreeding

–– Population migration: example with Population migration: example with mtDNAmtDNA analysisanalysis•• Analysis of ancient and contemporary materials: case of Analysis of ancient and contemporary materials: case of

ancient mummiesancient mummies

SpecificSpecific adaptations to adaptations to highhigh altitude in altitude in differentdifferent populationspopulations

From Beall et al, (2002) Proc. Natl Acad Sci 99, 17215-17218


•• Time of residence in HA:Time of residence in HA:Tibetans >Andeans >Europeans >HanTibetans >Andeans >Europeans >Han--Chinese > Chinese >

EthiopiansEthiopians•• Genetic drift: case of Andean Populations (languages, Inca Genetic drift: case of Andean Populations (languages, Inca

empire, empire, europeaneuropean admixture, ancestor diversity)admixture, ancestor diversity)–– Loss of genetic variation due to low population size: Loss of genetic variation due to low population size:

founder effect?founder effect?–– Gene flow: introduction of new genes by admixture Gene flow: introduction of new genes by admixture

inbreeding? inbreeding? –– Population migration: example with Population migration: example with mtDNAmtDNA analysisanalysis

•• Analysis of ancient and contemporary materials: case of Analysis of ancient and contemporary materials: case of ancient mummiesancient mummies

HumanHuman mitochondrial DNA Migrationsmitochondrial DNA Migrations

http://www.mitomap.org/mitomap/WorldMigrations.pdf

Mitochondrial DNA Mitochondrial DNA inheritanceinheritance

Major Major mtDNAmtDNA haplogrouphaplogroup branchesbranches

Human Mitochondrial DNAHuman Mitochondrial DNA

12S

16S

ND1

IM

ND2

CO I

CO II ATPase 8-6

CO IIIND3

ND4L

ND4

ND5

ND6

Cyt b

ADN mt

16569 pbQ

L

V

F

P

T

E

L

R

H S

G

K

S

D

CNAWY

OL

OHPH

PL

D-loop

9 pb-deletionHAPLOTYPE B

+Hae III 663HAPLOTYPE A

HAPLOTYPE C +Hinc II 13259

HAPLOTYPE D -Alu I 5176

12S

16S

ND1

IM

ND2

CO I

CO IICO III

ND3

ND4L

ND4

ND5

ND6

Cyt b

Q

L

V

F

P

T

E

L

R

H S

G

K

S

D

CNA

WY

OL

OHPH

PL

D-loop

ATPase 8/6

Cycle de Krebs

NADH+H+ NAD+

FMN

[FeS]

[FeS]

succinate

FAD

[FeS]

UQH2

UQH2 UQ.-

Cyt c1[FeS]

Cyt b566

Cyt b560

UQ.-

UQ

UQ

Cyt c Cyt c

CuA

Cyt aCuB-Cyt a3

H+fumarate

H+1/2O2+2H+

H2O

H+ H+H+

IVIIIIII

H+

ADP+Pi ATP

Matrice

V

Espace intermembranaire

H+

H+ H+ H+

H+H+

Fo

F1

H+

H+

• Oxydative phosphorylations

ADN nucléaireADN nucléaire77 1100 33 223939 101044 1010 1414

ADN ADN mtmt

ATPase-ATPsynthétase

cytochrome c oxydase

Ubiquinolcytochrome c

réductaseNADH

déshydrogénase

succinatedéshydrogénase


•• Time of residence in HA:Time of residence in HA:Tibetans >Andeans >Europeans >HanTibetans >Andeans >Europeans >Han--Chinese > Chinese >

EthiopiansEthiopians•• Genetic driftGenetic drift

–– Loss of genetic variation due to low population size: Loss of genetic variation due to low population size: founder effectfounder effect

–– Gene flow: introduction of new genes by admixture Gene flow: introduction of new genes by admixture inbreeding inbreeding

–– Population migration: example with Population migration: example with mtDNAmtDNA analysisanalysis•• Analysis of ancient and contemporary materials: case of Analysis of ancient and contemporary materials: case of

ancient mummiesancient mummies

Methods to distinguish Methods to distinguish Physiological/Environmental influence Physiological/Environmental influence

from Genetic selectionfrom Genetic selection

•• Compare differences between two isolated populationsCompare differences between two isolated populations

•• Investigate differences between monozygotic and Investigate differences between monozygotic and dizygoticdizygotictwinstwins

•• Compare a physiological trait to frequency of presence of a Compare a physiological trait to frequency of presence of a gene allele by linkage disequilibrium approachgene allele by linkage disequilibrium approach

•• Map chromosomal regions involved in regulation of Map chromosomal regions involved in regulation of physiological trait: FISH analysisphysiological trait: FISH analysis

•• Candidate gene approachCandidate gene approach















NorthernNorthern andand SouthernSouthern BlottingBlotting (1)(1)

SouthernSouthern BlottingBlotting (2)(2)

LOD SCORELOD SCORE

Lod score:Zθ=log10*(Lθ/Lθ0.5)

No Linkage Linkage

Recombination frequency 50%θ = 0.5

Genetic distance> 50 cMorgan

Recombination frequency 0%θ = 0

Genetic distance: 0 cMorgan








FISH: gene FISH: gene visualisationvisualisation on chromosomeson chromosomes

Examples of FISH experimentsExamples of FISH experiments

FISH: probe to telomeresFISH: probe to telomeresFISH: probe to a unique geneFISH: probe to a unique gene

on chromosome 7on chromosome 7

Mutation Mutation detectiondetection withwith microarraysmicroarrays(AFFYMETRIX)(AFFYMETRIX)








BirthBirth weightweight andand Adaptation to AltitudeAdaptation to Altitude


EndothelinEndothelin 11


EndothelinEndothelin 1, a potent vasoconstrictor is differentially regulated by preg1, a potent vasoconstrictor is differentially regulated by pregnancy and nancy and chronic hypoxia in Andean versus European residents of High Altichronic hypoxia in Andean versus European residents of High Altitude. tude. SNPsSNPs in in the ETthe ET--1 gene also differ in Andeans compared to low1 gene also differ in Andeans compared to low--altitude populations. altitude populations. Example of natural selection acting on one of the HIFExample of natural selection acting on one of the HIF--targeted genes.targeted genes.

Other candidate genes near HIFOther candidate genes near HIF--regulated genes exhibiting different allele regulated genes exhibiting different allele frequencies between Quechua frequencies between Quechua NahuaNahua and Eastand East--Asians identified with the Asians identified with the AffymetrixAffymetrix chip : NOSII, PHD3, chip : NOSII, PHD3, αα--adrenergic receptoradrenergic receptor

From Mortimer et al, (2004) Pharmacology and Therapeutics, 101: 183-192

PotentialPotential geneticgenetic influence on HAPEinfluence on HAPE((HighHigh--AltitudeAltitude PulmonaryPulmonary ŒŒdemadema))

AngiotensinAngiotensin convertingconverting enzyme enzyme andandgeneticsgenetics atat highhigh altitudealtitude

AlleleAllele D: D: DeletionDeletionAlleleAllele I: I: Insertion of 287 Insertion of 287

bpbp in intron 16in intron 16

Mitochondrial DNAMitochondrial DNA

12S

16S

ND1

IM

ND2

CO I

CO II ATPase 8-6

CO IIIND3

ND4L

ND4

ND5

ND6

Cyt b

ADN mt

16569 pbQ

L

V

F

P

T

E

L

R

H S

G

K

S

D

CNAWY

OL

OHPH

PL

D-loop

9 pb-deletionHAPLOTYPE B

+Hae III 663HAPLOTYPE A

HAPLOTYPE C +Hinc II 13259

HAPLOTYPE D -Alu I 5176

-- 55--15% EPA (excessive 15% EPA (excessive PolycythemiaPolycythemiaof Altitude) incidence in Boliviansof Altitude) incidence in Bolivians--55--15% non B 15% non B HaplotypesHaplotypes (A or C)(A or C)

-- A or C A or C mtDNAmtDNA haplogroupshaplogroups are not found are not found in Tibetans rarely suffering of EPAin Tibetans rarely suffering of EPA

-- Different Different SNPsSNPs in B versus A or C in B versus A or C haplotypesshaplotypess in CO I and COIIin CO I and COII

-- Regulation of COX synthesis by HIFRegulation of COX synthesis by HIF

-- Similarities between development of EPA Similarities between development of EPA and of some mitochondrial diseases and of some mitochondrial diseases during adult life. during adult life.

0%

20%

40%

60%

80%

100%

C1 C2 C3 EPA I EPA II C total EPA I+II

%C

%A

%B

HAPLOGROUP DISTRIBUTION HAPLOGROUP DISTRIBUTION IN CONTROLS AND EPA PATIENTSIN CONTROLS AND EPA PATIENTS

Excessive Excessive ErythrocytosisErythrocytosis of Altitude(EPA) in relationof Altitude(EPA) in relationto to mtDNAmtDNA haplogroupshaplogroups in in BolivianBolivian Aymaras?Aymaras?

CONCLUSIONSCONCLUSIONS##Many arguments converge to convince us that genetic eventsMany arguments converge to convince us that genetic eventshave occurred to better adapt humans in high altitude areas afthave occurred to better adapt humans in high altitude areas after their er their initial settlement. Genetic adaptation is very likely different initial settlement. Genetic adaptation is very likely different from one from one place to the other.place to the other.

##In spite of many efforts, the number of conclusively identified In spite of many efforts, the number of conclusively identified genes genes remains low. A lot more is to be done to understand the differenremains low. A lot more is to be done to understand the different paths t paths that nature has found to improve life in High Altitude! that nature has found to improve life in High Altitude!

## New tools are there and being further developed to accelerate tNew tools are there and being further developed to accelerate this his type of research due to knowledge of whole human genometype of research due to knowledge of whole human genome

##One of the most difficult tasks remains the selection of adequatOne of the most difficult tasks remains the selection of adequate e populations: populations:

--isolated populations become rareisolated populations become rare--incidence of external factors to develop an adaptation or a diseincidence of external factors to develop an adaptation or a disease ase and hence risk of poor selection of subjects to be analyzedand hence risk of poor selection of subjects to be analyzed--an excellent knowledge of the an excellent knowledge of the physiophysio--pathological status of these pathological status of these populations is an absolute requirement populations is an absolute requirement

•• Catherine Catherine GodinotGodinot•• Hélène Hélène SimonnetSimonnet•• Eric Eric HervouetHervouet•• Jocelyne Jocelyne DemontDemont•• Franck Franck DragounoffDragounoff•• Elodie Elodie CoujardCoujard de de

LaplancheLaplanche

•• Institut Bolivien de Biologie Institut Bolivien de Biologie d’Altitude, La d’Altitude, La PazPaz, BOLIVIE, BOLIVIE–– Enrique VargasEnrique Vargas–– Fabrice RossignolFabrice Rossignol–– ElfrideElfride BalanzaBalanza–– EnmaEnma RuizRuiz–– Mercedes VillenaMercedes Villena–– Ivette Ivette RodriguezRodriguez

QuickTime™ et undécompresseur TIFF (LZW)

sont requis pour visionner cette image.

HighHigh altitude altitude andand capillarycapillary densitydensity in in placentasplacentas

Immunohistochemical staining using antiCD34 staining and hematoxylin background stain

Tyrosine Tyrosine HydroxylaseHydroxylase

Genetic engineering

– Restriction site maps•(0,001 à 0,02 Megabases)

– Cloning•vectors : plasmids, phages, cosmids•(insert size : 0,001 à 0,05 Megabases

Physical map

Classical genetic

– Lod score•1 cMorgan ~ 1 Megabase

– Gene localization on chromosomes (FISH)

•precision ~ 10 Megabases

Genetic map

Traditional genetic toolsTraditional genetic tools

Mutation Mutation detectiondetection withwith syntheticsynthetic probesprobes

Variations physiopathologiques de la Variations physiopathologiques de la biogenèse mitochondrialebiogenèse mitochondriale

• Développement : exemple de C. elegans• Vieillissement• Exercice musculaire• Maladies mitochondriales : prolifération (RRF) ou

déplétion de l’ADNmt• Baisse des activités OXPHOS dans la plupart des

cancers sauf dans les oncocytomes

Evolution du contenu en Evolution du contenu en ADNmtADNmtau cours de la vie de au cours de la vie de C. C. eleganselegans

Selon Tsang et Lemire (2002)

Documents

HUMAN GENETIC ADAPTATION TO HIGH ALTITUDE · • Compare differences between two isolated populations ... -Similarities between development of EPA and of some mitochondrial diseases