MIGRANT STUDIES

Ronald E. LaPorte, Ph.D.

Director, Disease Monitoring and Telecommunications WHO

Collaborating Center, Professor of Epidemiology

Questions

• What is a Migrant Study?

• How do Migrant Studies differ from Admixture Studies?

• What is the future for Admixture and Migrant Studies?

Migrants

pilgrimrefugeeconquerorsdisplaced people

Migrant Studies

Studies taking advantage of migration to one country by those from other countries with different physical and biological environments, cultural background and/or genetic makeup, and different morbidity or mortality experience.

From (KOFF)1967 PITTSBURGH

Growth of Racial/Ethnic Groups in U.S.A.

0

20

40

60

80

100

120

AsianHispanicOtherIndianBlackWhite

Percent

The migration of human populationprovides a tool for the study of therespective roles of host and environmentalfactors in the development of disease.

05

1015202530

Rise and Fall of Migrant Studies

Migratory Patterns

Jan Dorman

Ireland,1817Germany,1920

Poland, 1900

Migration Patterns

Trevor Orchard

England, 1979

Migratory Pattern

Ron LaPorte

France, 1819

Germany, 1880

Quebec, 1820

Buffolo,NY Pittsburgh,PA

1993 Refugees to U.S.

Former Soviet Union 52,000

East Asia52,000South East Asia 7,000

Africa7,800

Latin America 3,500

EasternEurope,1,500

MIAMI

HAVANA

1970s1950s

Migrant Studies

SourcePopulation

Migrant Pop

HostPopulation

Incidence of Disease X in source, host, and migrant populations

Environmental etiology

Incidence of Disease X in source, host, and migrant populations

Genetic etiology

Migrants are almost neverrepresentative of their nativepopulations

Existing Migrant Data

Some example of IDDM incidence per 100000

Nationality

Russian 5 (Siberia) 9 (Estonia)

Norwegian 22 (Norway) 8 (Iceland)

French 8 (4 areas) 8 (Quebec)

Chinese 7(Shanhai) 3(Hawaia)

Japanese 2 (some areas) 3 (Hawaia)

Jewish 6 (Israel) 15 (Canada)Mexican 1(Some areas) 10 (Colorado)

Source Migrant

Differences in Incidence, Migration vs Geographic

Variation Ratios Absolute

Differences

Migration 3-6 16

Geographic Differences

50 34

Questions

• What is a Migrant Study?

• How do Migrant Studies differ from Admixture Studies?

• What is the future for Admixture and Migrant Studies?

Admixture studies

Hybrid populations

Parent population

1

H1

H2

H3

Parent population

2

Incidence of Diseases X in source and hybrid populations

Correlation of Incidence of Disease X and admixture proportion

Admixture proportion

Incidence

AB C

DE

FG H

I

Migration Time Line

1st Generation

Environmental“Shower”

Genetic Change

3rd Generation

2nd Generation

Cultural Change

ClimateViruses

ShowersCulture

Genetics

Full Assimilation

Migration Time Line

1st Generation

Environmental“Shower”

Genetic Change

3rd Generation2nd Generation

Cultural Change

Beginning Loss of Language Changes in Diet

IDDM in Asian Populations

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JPN

TA

IWA

Tai

land

Kor

ea

Haw

aii(

japa

nese

)

CA

(Kor

eian

s)

per 100000

Ten fold Difference

Questions

• What is a Migrant Study?

• How do Migrant Studies differ from Admixture Studies?

• What is the future for Admixture and Migrant Studies?

Heritage Research: The Next Generationof Migrant Studies

Heritage studies

Genetic factors

Parent population

1

H1

H2

H3

Environmental Factors

IDDM Incidence in Latin America

02468

1012

Sp

ain

Bra

zil

Cu

ba

Ch

ili

Per

u

Incidence per 100 000

SPAIN

NORTHandSOUTHAMERICA

Iberian - heritage collaboration