1. Swedish Twin Registry - STR
HISTORY
Started by Lars Friberg and Rune Cederlöf in the late 1950’s
Church records of twin births
All identified same sex twins contacted during the 1960’s
Today: all alive Swedish born twins aged 10 or more have been contacted and asked for participation

2. Steering group
Steering group: Patrik Magnusson (director) Nancy Pedersen, Paul Lichtenstein, Martin Schalling, Magnus Svartengren, Maria Feychting, Laura Fratiglioni, Göran Pershagen, Johan Askling, Tomas Ekström
Evaluation of applications
Meetings 4 times per year

3. The Swedish Twin Registry –
Historical cohort compilations and contacts
Birth cohort
1960
1990
2000
2010
1970
1980

4. Current ascertainment into STR
Since 2004 we systematically contact parents to Swedish born twins when they turn 9 years of age
Request to participate in STR – broad consent
Screen for somatic and mental health problem
High participation rate (70-80%)
Follow-up’s at 12, 15, 18 years

5. Recent “Landmark”
All adult Swedish born twins 10 years or older have now been contacted for participation with general questionnaire and DNA donation request
in the register
have zygosity
The largest twin register in the world

6. Data Paper Questionnaires Telephone interviews (SALT 1998-2002)
Web questionnaires (2005 and onwards)
Health check-up (TwinGene, CATSS, SATSA)
Health registers (SoS)
DNA (N=50 000)
GWAS (N=33 000, not counting MZ twice)
Serum (N=15 000)
Blood biochemistry (TwinGene, SATSA)
Computer tests (cognition, time-consistency)

7. GWAS Older cohort (1911-1958): Younger cohort (1994 -- )
Illumina GWAS array N =
Excl. redundant MZ genomes N =
Genotyped in Uppsala (SNP&SEQ Tech) 2008, 2011, 2015
Younger cohort ( )
Illumina GWAS array N =
Excl. redundant MZ genomes N=11 000
Genotyped in Uppsala (SNP&SEQ Tech) 2015

8. Serum measurements All of TwinGene (N=12600) Subsets
HDL, LDL, TC, TG, CRP, Hb, HbA1c, Glucose, ApoA1, ApoB
ACPA (Lars Klareskog)
Total IgA (Lennart Hammarström)
Creatinine, Cystatin C (Per Svensson)
Subsets
LpPla2, aPC, aOxCl (Ulf de Faire, Johan Frostegård)
PCSK9 (Anders Hamsten)
Proteomics (SciLife Lab Protein atlas)
Metabolomics (HPLC Mass spec)
Serum is an available but limited resource - should be used thoughtfully!

9. Epigenetics Key observations: Measure Epigenetics:
Gene expression differs between cell types within individual
MZ twins - discordant
Gene expression influenced by environment
Measure Epigenetics:
DNA methylation, histone acetylation etc.
Confounding from Genetics:
MZ twins may provide remedy!

10. Applying for new projects
STR steering committee meets 4 times/year
Short application + CV + ethics permission
metadata + questionnaires assessable for free
Blood, serum and DNA stored in biobank
Phenotypes