The genetics of osteoporosis - · PDF fileThe genetics of osteoporosis ... •hand malformations. nail dysplasia ... Microsoft PowerPoint - postgratuaat2016 Author: wim van hul

The genetics of The genetics of osteoporosisosteoporosis

A A paradigmparadigm forfor geneticgenetic studies studies of a complex of a complex diseasedisease in the last in the last

Wim Van Hul

Department of Medical Genetics

University of Antwerp

of a complex of a complex diseasedisease in the last in the last 3 decades3 decades

Changes in bone massChanges in bone massChanges in bone massChanges in bone mass

Ma

ss

Male

Bo

ne M

10 20 30 40 50 60 70 80

Female

Age (Years)

OsteoporosisOsteoporosisOsteoporosisOsteoporosis

Definition

Osteoporosis is defined by the World Health Organization(WHO) in women as a bone mineral density 2.5 standard mineral density 2.5 standard deviations (T-score) below peak bone mass (20-year-old healthy female average) as measured by DXA

OsteoporosisOsteoporosisOsteoporosisOsteoporosis

risk factors:*Gender* Age* Early menopause in women* Amenorrhea* Low testosterone levels in men* Low calcium intake* Race and ethnicity * Low calcium intake* Race and ethnicity * Small or thin body frame* Excessive alcohol use * Smoking* Inadequate physical exercise* Certain endocrine disorders * Chronic diseases of the lungs, kidneys, stomach, and

intestines* Prolonged use of medicines like steroids, antacids,

anticonvulsants

ChangesChanges in in bonebone massmassChangesChanges in in bonebone massmass

Hendrickx et al. Nature Rev Reumat, 2015

HeritabilityHeritabilityHeritabilityHeritability

Bone mineral density

46 – 84 %

hip : 73 %hip : 73 %spine: 66 %

Bone size

hip: 69 %

spine: 60 %

Hip axis length62 %

Genetic research of osteoporosisGenetic research of osteoporosis

1980: Genetic studies on osteoporosis as a quantitative trait are relevant

Standard approachStandard approachassociation studiesbut no – large cohorts with detailed phenotypical data

- no data on polymorphisms in human genome

- no techniques for high throughput genotyping

How to identify genes for complex traitsHow to identify genes for complex traits

Identification of genes for relevant monogenic conditions1. functional candidate gene approach2. positional cloning of relevant monogenic

conditionsAssociation studies

3. candidate genes

1980 1990 2000 2010

3. candidate genes4. genome wide association studies


Identification of genes for relevant monogenic conditions1. functional candidate gene approach2. positional cloning of relevant monogenic

conditionsAssociation studies

3. candidate genes

1980 1990 2000 2010


1. Functional candidate gene approach1. Functional candidate gene approach1. Functional candidate gene approach1. Functional candidate gene approach

Collagen genes

causative for conditions with decreased bone mineral density and brittleness of bonemineral density and brittleness of bone

Chu et al. Nature 1983Internal deletion in a collagen gene in a perinatal lethal form of osteogenesis imperfecta.


Identification of genes for relevant monogenic conditions1. functional candidate gene approach2. positional cloning of relevant monogenic conditions

Association studies3. candidate genes

1980 1990 2000 2010





1980 1990 2000 2010


Sclerosing bone dysplasiasSclerosing bone dysplasiasSclerosing bone dysplasiasSclerosing bone dysplasias

International working group on the

classification and nosology of

constitutional disorders of boneconstitutional disorders of bone(Martigny, 2005)

About 40 different clinical entitieswith increased bone density

Increased bone formationIncreased bone formationIncreased bone formationIncreased bone formation


Van Buchem disease

Hyperostosis corticalis generalisata

-- enlargement of the jaw

- thickening of the skull

– > Nerve encroachment

• facial nerve palsy

• hearing loss

van Buchem patient Control

Van Buchem diseaseVan Buchem diseaseVan Buchem diseaseVan Buchem disease

Incidence : very low

- 25-30 patients worldwide- 25-30 patients worldwide

- small village in The Netherlands

11 patients

Ethnic isolateEthnic isolateEthnic isolateEthnic isolate

• Island until 1941

• Geographically, religiously and professionally isolated

• In 1637: 151 inhabitants• In 1637: 151 inhabitants

• Currently 16.000 inhabitants

• Most inhabitants related to each other

Dutch van Buchem familyDutch van Buchem familyDutch van Buchem familyDutch van Buchem family

I

II

III

IV

V

13

123

2 4 5 9 10 11

6 7 81

V

VI

VII

VIII

IX

X


Van Buchem disease

Differential diagnosisDifferential diagnosisDifferential diagnosisDifferential diagnosis

Sclerosteosis

• gigantism

• more severe character• more severe character

• hand malformations

nail dysplasia

syndactylysyndactyly

Gene identificationGene identificationGene identificationGene identification2758 bp

23'

acagACG

220 bp 422 bp

AAGgtat

ATG TAG

5'

SOST

Brazilian sclerosteosismutation

C A A A G G T T T G G G G T Gpatient

Senegalese sclerosteosis mutation

American sclerosteosismutation

normal C A A A G G T A T G G G G T G

C A A G T G A T G G C G A

C A A G T G G T G G C G A

T G G T G G T G A C C T A

T G G T G G C G A C C T A

SOST


Van Buchem disease (SOST)

Sclerosteosis (SOST)

Endosteal hyperostosisEndosteal hyperostosisEndosteal hyperostosisEndosteal hyperostosis

High Bone MassHigh Bone Mass--phenotypephenotypeHigh Bone MassHigh Bone Mass--phenotypephenotype

•2 families

•Johnson et al. 1997

•Boyden et al. 2002•Boyden et al. 2002

•Cortical thickening of the long bones

•Phenotypical differences: mandible

torus palatinus

•Same LRP5 mutation (G171V)

LDL-Receptor-Related protein 5 (LRP5)LDL-Receptor-Related protein 5 (LRP5)

G171V

Osteoporosis pseudoglioma syndromeOsteoporosis pseudoglioma syndromeOsteoporosis pseudoglioma syndromeOsteoporosis pseudoglioma syndrome

-Autosomal recessive

-Juvenile osteoporosis

-Congenital blindness-Congenital blindness

Mutations in LRP5 geneMutations in LRP5 geneMutations in LRP5 geneMutations in LRP5 gene

1282C>TR428X

29G>AW 10X

1467delGD490fs

2150insTD718X

2557C>TQ853X

3804delAE1270fs

2305delGD769fs

1999G>AV667M

1481G>AR494Q

1453G>TE485X

1708C>TR570W

2202G>AW734X

Osteoporosis-pseudoglioma syndrome (OPPS)


Van Buchem disease (SOST)Sclerosteosis (SOST)

Endosteal hyperostosis (LRP5)

Aut dom osteosclerosis (LRP5)“Van Buchem” (LRP5)

LRP5LRP5

G171V

LRP5LRP5LRP5LRP5

G171V

A242TA214T

G171R

D111Y

T253I

A214TA214V

Canonical Wnt signalingCanonical Wnt signaling

Sclerostin-LRP5Sclerostin-LRP5

Genetic variation within SOST and Genetic variation within SOST and LRP5 genesLRP5 genes










Genetic research of osteoporosisGenetic research of osteoporosis

1980: Genetic studies on osteoporosis as a quantitative trait are relevant

Standard approachStandard approachassociation studiesbut no – large cohorts with detailed phenotypical data

- no data on polymorphisms in human genome

- no techniques for high throughput genotyping

Since 1990s: all three problems were getting solved slowly




1980 1990 2000 2010


1994: osteoporosis gene!1994: osteoporosis gene!1994: osteoporosis gene!1994: osteoporosis gene!

1994: osteoporosis gene!1994: osteoporosis gene!1994: osteoporosis gene!1994: osteoporosis gene!

250 healthy Caucasian twins (Australia)

BMD measurements at different sites

75% of genetic effect on bone density explained75% of genetic effect on bone density explained

1997199719971997

Nature 387: 106 (1997)

Erratum

“We re-examined the original samples and found that “We re-examined the original samples and found that in a proportion of these twins the genotype on new DNA differed from the earlier DNA samples.”

It seems most likely that the misclassifications arose from misgenotyping of DNA samples between extraction and PCR analysis.

1450 citations

Association studiesAssociation studiesAssociation studiesAssociation studies

– Osteopetrosis

– Pycnodysostosis

– Camurati-Engelmann

Carbonic anhydrase II

H+ATPase/CLCN7/GL

Cathepsin K

TGFB1– Camurati-Engelmann

– Van Buchem/Sclerosteosis

– High Bone Mass

– Familial Expansile osteolysis

– Paget’s disease

TGFB1

SOST

LRP5

RANK

OPG/SQSTM1

Association studiesAssociation studiesAssociation studiesAssociation studies

– Osteopetrosis

– Pycnodysostosis

– Camurati-Engelmann

Carbonic anhydrase II

H+ATPase/CLCN7/GL

Cathepsin K

TGFB1– Camurati-Engelmann

– Van Buchem/Sclerosteosis

– High Bone Mass

– Familial Expansile osteolysis

– Paget’s disease

TGFB1

SOST

LRP5

RANK

OPG/SQSTM1

Rotterdam

Aberdeen

Aarhus

Cambridge

Prospective meta-analyses of osteoporosis candidate genes

“GENOMOS” QLK6-CT-2002-02629

(Genetic Markers for Osteoporosis)

EU FP5 sponsored, 3 mio euro, 2003-2007

2

3

5

6

Total number of

subjects: 21.040

14.399 women

5.587 men

Participants:

AG Uitterlinden, Netherlands

SH Ralston, United Kingdom

BL Langdahl, DenmarkRotterdam

Antwerp

Barcelona

Firenze

Ioannina

Oxford

61

7

9

4

8

4.575 fractures

Coordinating Centre: Department of Internal Medicine, Erasmus MC, Rotterdam (AG Uitterlinden)

BL Langdahl, Denmark

ML Brandi, Italy

J Reeve, United Kingdom

A Carey, United Kingdom

W Van Hul, Belgium

JPA Ioannidis, Greece

A Diez-Perez, Spain








1980 1990 2000 2010





1980 1990 2000 2010


EUEUEUEU----FP7 project: GEFOSFP7 project: GEFOSFP7 project: GEFOSFP7 project: GEFOS (start march 2008)

= GENOMOS study population= GENOMOS study population= GENOMOS study population= GENOMOS study populationNumber of subjects:GENOMOS: >150,000GWA: 40,000 = idem + GWA= idem + GWA= idem + GWA= idem + GWA

= idem, under negotiation / in development= idem, under negotiation / in development= idem, under negotiation / in development= idem, under negotiation / in development

One single study has insufficient power to identify genomeOne single study has insufficient power to identify genome--wide significant signalswide significant signals

LUMBAR SPINE BMD

N=5000N=5000

5 x 10-8

• Rotterdam Study

Rivadeneira et al., ASBMR sept 2008

As sample size increases genomeAs sample size increases genome--wide significant signals become gradually evidentwide significant signals become gradually evident

LUMBAR SPINE BMD

N=6200N=6200

5 x 10-8

• Rotterdam Study

• ERF Study

LRP5LRP5


Four novel loci exceed GWS threshold, many others are close Four novel loci exceed GWS threshold, many others are close

1p

36

1p

36

C6

ôrf

10

C6

ôrf

10

RANKRANK--LL

Novel: Chr 1p, 7p, 7q and 12p

OPGOPG

LUMBAR SPINE BMD

N=18500N=18500

5 x 10-8

• Rotterdam Study

• ERF Study• Twins UK

• deCODE Genetics• Framingham Study

1p

36

1p

36

MHCMHC

C6

ôrf

10

C6

ôrf

10

LRP5LRP5


FEMORAL NECK BMD

5 x 10-8

Three novel loci exceed GWS threshold, many others are closeThree novel loci exceed GWS threshold, many others are close

C6

ôrf

10

C6

ôrf

10

OPGOPG LRP5LRP5

RANKRANK--LL

Novel: Chr 1p, 5q and 7q

N=18500N=18500

• Rotterdam Study

• ERF Study• Twins UK

• deCODE Genetics• Framingham Study Rivadeneira et al., ASBMR sept 2008

Recent metaRecent meta--analysis of GWASanalysis of GWASRecent metaRecent meta--analysis of GWASanalysis of GWAS

- 140 research teams- 130.000 individuals- 56 genes for BMD- 14 genes for fracture risk

? ? ? ?? ? ? ? ?

? ? ? ? ? ? ?~95% ~95% of varianceof variance

? ? ? ? ? ? ? ? ? ?

Polymorphisms with subtle effects

Tra

it P

op

ula

tio

n F

req

ue

ncy

Mutations with severe effects

Mutations with severe effects

Rare Common Rare

Recent reports:GWAS: Lancet, NEJMGENOMOS: JAMA (LRP5)

Genetic architecture of BMDGenetic architecture of BMD

? ? ? ? ? ? ? ? ? ?

? ? ? ? ? ? ? ? ? ? ?? ? ? ? ? ? ? ? ? ? ? ?

? ? ? ? ? ? ? ? ? ? ? ? ?? ? ? ? ? ? ? ? ? ? ? ? ? ?

? ? ? ? ? ? ? ? ? ? ? ? ? ? ?

? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?

? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?

? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?Tra

it P

op

ula

tio

n F

req

ue

ncy

Low High

LRP5

COL1A1

Etc.

LRP5

SOST

CICN7

Etc.

BMD

LRP5LRP5 OPGOPG MHCMHC RANKLRANKL

C6orf10C6orf10 ESR1ESR1 LRP4LRP4 HOXC4/6HOXC4/6

Genetic architecture of bone mass

Boudin et al. Mol Cell Endocrinol. 2015

BMD-associated genes

Hendrickx et al. Nature Rev Reumat, 2015

ConclusionsConclusionsConclusionsConclusions

• Study of large cohorts is essential

=> Importance of worldwide collaborations

• Genes involved in monogenic disease often role in

complex formscomplex forms

• GWAS: new loci and genes

• Only low percentage of phenotypical variation explained by currently identified loci

• Role for CNVs or rare variants?

• Complete picture: putative applicability of these data

Documents

The genetics of osteoporosis - · PDF fileThe genetics of osteoporosis ... •hand malformations. nail dysplasia ... Microsoft PowerPoint - postgratuaat2016 Author: wim van hul