Existing data sources for clinical epidemiology: Danish registries for studies of medical genetic diseases

Figures & data

Table 1 Overview of national medical genetic registries in Denmark

Genetic registry (Danish name)	Description	Registration start/end	Data administrator/contact	Other details
Danish Cytogenetic Central Register^Citation7,Citation8 (Dansk Cytogenetisk Centralregister)	Prenatal and postnatal diagnostic chromosomal analyses	1960 to present, nationwide	Aarhus University Hospital, Skejby http://www.auh.dk/om+auh/afdelinger/klinisk+genetisk+afdeling/links/dccr	Over 300,000 registrations as of January 2010 and approximately 10,000 new registrations each year
Hereditary Nonpolyposis Colorectal Cancer Register^Citation11,Citation12 (HNPCC-registret)	Hereditary NonPolyposis Colorectal Cancer (HNPCC) and other inheritable/familial colorectal cancers not registered in the Danish Polyposis Register	1991 to present, nationwide since 1995	Hvidovre Hospital http://www.hvidovrehospital.dk/menu/Afdelinger/Gastroenheden/HNPCC/	Over 5103 families/76,300 individuals registered (among these, 2582 families/20,900 individuals have undergone genetic testing)
Hereditary Breast and Ovarian Cancer Registry^Citation13 (HBOC-registret)	Hereditary Breast (and Ovarian) Cancer	1999 to present, nationwide	Danish Breast Cancer Cooperative Group. Contact: DBCG Secretariat, Rigshospitalet 2501, Blegdamsvej 9, DK-2100 Copenhagen Email [e-mail] www.dbcg.dk For a 2008 report of the registry, see http://www.dbcg.dk/Foredrag/4%20DBCGs%20database%20SM.pdf	8900 registered families, each with data on female family members referred for surveillance due to an increased risk of breast and/or ovarian cancer; questionnaires on lifestyle and earlier use of mammography for some of these
Danish Polyposis Register (Polypose-registeret)	Nationwide registry of polyposis patients and their relatives	1976 to present, nationwide	Hvidovre Hospital Email [e-mail] http://www.cancer.dk/NR/exeres/7B1BB82C-5205-4B0A-A916-366ED072C7A2.frameless.htm	Persons with > 100 colonic polyps and their families As of August 2011, 200 registered families; 622 patients (291 alive); and 768 first-degree relatives
Danish Huntington Register (Det Danske Huntington Register)	Huntington’s disease	1940, electronic records from 1980 to present, nationwide	Institute for Cellular and Molecular Genetics, Panum Institute, University of Copenhagen Contact person, Sven Asger Sørensen Email [e-mail] http://huntingtons.dk/omlhs/LHCNyt/sidstenr.asp	12,000 registrations of patients and 600 families with HD or at risk of HD
Danish Cystic Fibrosis Patient Registry^Citation24,Citation26 (Cystisk Fibrose Register Denmark)	Patients with CF (including data on survival, lung function, BMI, and infections)	2001 to present, nationwide	Contact person, Hanne Vebert Olesen, Aarhus University Hospital (Skejby), Department of Pediatrics Email [e-mail] http://ecfs.eu/files/webfm/webfiles/File/ecfs_registry/ECFSPR_Report0809_v320l2.pdf	451 registered (among these 442 living) CF patients as of December 31, 2009
Nordic Database for Rare Diseases^Citation49 (Databasen for Sjældne Handicap RAREDIS)	Nordic Rare Diseases database (Denmark, Sweden, Norway, Finland, and Iceland)	2006 to present, compulsory registration since 2007, nationwide	Danish contact, Hanne Hove Department of Clinical Genetics, Rigshospitalet Email [e-mail] https://raredis.eu/	1500 registered patients. Ongoing research projects to date: • scaphocephaly (variables include head circumference of parents and offspring, and surgical information) • neurofibromatosis • osteogenesis imperfecta • Angelman syndrome
Danish Family Archive for Genetic Eye Diseases (Dansk Familiearkiv for Arvelige Øjensygdomme)	Nationwide umbrella register of heritable eye diseases (over 100 different conditions represented, eg, retinitis pigmentosa described below)	1985 to present, nationwide	The National Eye Clinic for the Visually Impaired, Kennedy Center, Rigshospitalet (previously known as Statens Øjenklinik) Contact person, Thomas Rosenberg Email [e-mail]	45,000 registrations including about 3000 families, as of 2012. Detailed records of pedigrees including all known mutations Approximately 400 new registrations each year. Variables include CPR number, name, date of birth, position in the family tree, signature of the affected, unaffected, or carrier patients, mode of inheritance, mutation(s), and the laboratory that identified the mutation
Danish Retinitis Pigmentosa Register^Citation50 (Dansk Retinitis Pigmentosa [RP] register)	Retinitis pigmentosa	1990 to present, nationwide	The National Eye Clinic for the Visually Impaired, Kennedy Center, Rigshospitalet (previously known as Statens Øjenklinik)	2870 registrations (as of July 2011) and approximately 50 new registrations each year Variables include age at debut, differential diagnoses (retinitis pigmentosa under groups), complexity, and others
vHL registry (vHL-registret)	von Hippel-Lindau disease	Nationwide, 1930–2010	Cellular and Molecular Medicine, Panum Institute, Blegdamsvej 3, DK-2200 København N Contact person, Søs Marie Luise Bisgaard, Email [e-mail]	56 families with vHL. Registrations on organ manifestations, mutations, disease status
Fabry registry (Mb Fabry registeret)	Fabry disease	Nationwide	Institute for Cellular and Molecular Genetics Contact person, Lis Hasholt Email [e-mail]	Approximately 40 registered cases
Danish Hereditary Angioedema Registry	Hereditary angioedema	Registration to Odense Patient data Explorative Network (OPEN) since 2011, Nationwide	Department of Dermatology, Odense University Hospital Contact person, Anette Bygum Email [e-mail]	95 HAE patients registered; 8 acquired angioedema patients registered; includes clinical data as well as a biobank Previously contributed data to the European HAE registry
Danish Porphyria Registry (Porfyriregister)	Hereditary porphyria	Started approximately 1969	Odense University Hospital Contact person, Jens Michael Hertz Email [e-mail]	Reference: With TK 1969^Citation51

Abbreviations: BMI, body mass index; CF, cystic fibrosis; HAE, hereditary angioedema; HD, Huntington’s disease; vHL, von Hippel-Lindau disease.

Table 2 Danish departments of clinical genetics and other specialized departments and centers

Department/center (Danish name)	Data/administrative system	Address and internet homepage	Contact	Other details
Departments of clinical genetics
Clinical Genetics, Aarhus	Langtved database 1991 - to present	Aarhus University Hospital Brendstrupgårdsvej 21 C, 8200 Aarhus N http://www.en.auh.dk/departments/cancer+and+inflammation+centre/department+of+clinical+genetics? and http://www.en.auh.dk/departments/cancer+and+inflammation+centre/department+of+clinical+genetics	Chief of Staff, Ida Vogel, MD, PhD Email [e-mail]	>20,000 patients registered; variables registered in Langtved include CPR number, family relationships, chromosomal/molecular analyses undertaken, and diagnosis of genetic disease
Clinical Genetics, Aalborg	Langtved database	Aalborg University Hospital Ladegårdsgade 5, Building E, 5th floor, 9000 Aalborg Email [e-mail] http://www.aalborgsygehus.rn.dk/Afdelinger/KraeftOgDiagnostikcenter/Afdelinger/Klinisk+Genetisk+Afdeling/	Professor and Chief of Staff, Michael B. Petersen Email [e-mail]	Approximately 2500 patients registered since 2009
Clinical Genetics, Odense	Langtved database	Odense University Hospital Søndre Boulevard 29, DK-5000 Odense C http://www.ouh.dk/wm290661	Chief of Staff, Lotte Krogh Email [e-mail]	National site for diagnostics and treatment of porphyria and hereditary hemorrhagic telangiectasia, also known as Osler-Weber-Rendu Disease
Clinical Genetics, Vejle Hospital	Genetik DB administration system	Vejle Hospital, Kabbeltoft 25, 7100 Vejle http://www.sygehuslillebaelt.dk/wm24252l	Chief of Staff, Anders Bojesen Email [e-mail]	Approximately 8500 registered patient cases and 21,600 test results (eg, chromosomal and DNA analyses)
Clinical Genetics, Copenhagen	OPUS, GR, and KLIQ systems for data registration and administration	Rigshospitalet, Afsnit 4062 Blegdamsvej 9, 2100 Copenhagen www.kliniskgenetik.rh.dk	Chief of Staff, Professor Anne-Marie Gerdes Email [e-mail]
Other specialized departments/centers
Center for Rare Diseases (Center for Sjældne Sygdomme), Aarhus	Patient Administrative System	Aarhus University Hospital Brendstrupgårdsvej 21 C, 8200 Aarhus N http://www.css.auh.dk	Centre for Rare Diseases (Center for Sjældne Sygdomme), Aarhus Email [e-mail]	Center in the Department of Pediatrics; about 2000 patients registered with the center. Diagnosis, follow-up, treatment and counseling of children with a rare condition/disease and adults with Marfan, von Recklinghausen, Prader-Willi, Spielmeyer-Vogt and vascular Ehlers-Danlos syndromes
Clinic for Rare Handicaps (Klinik for Sjældne Handicaps), Copenhagen	OPUS, GR, and KLIQ systems for data registration and administration	Rigshospitalet, Afsnit 4062 Blegdamsvej 9, 2100 Copenhagen www.kliniskgenetik.rh.dk	Professor and Chief of Staff Anne-Marie Gerdes Email [e-mail]	Center within the Department of Clinical Genetics, Copenhagen
Kennedy Center, Copenhagen	Cosmic (patient administration program); PASS clinical genetic database (pedigrees); and progeny (program for family archives)	Juliane Marie Center, Rigshospitalet, Gl Landevej 7, 2600 Glostrup http://www.kennedy.dk/	Director, Professor Karen Brøndum-Nielsen Email [e-mail]	National research center for genetics, visual impairment, and mental retardation. Centers: Fragile X Center PKU Center, Rett syndrome center, The National Eye Clinic
Department of Dermatology, Aarhus	Patient Administrative System	Aarhus University Hospital, PP Ørums Gade 11, 8000 Aarhus C http://www.auh.dk/om+auh/afdelinger/dermato-venerologisk+afdeling+s	Mette Sommerlund, Dermatologist, specialist in genodermatoses	Dermatological focus on genodermatoses: ichthyosis, keratoderma palmoplantaris, epidermolysis bullosa, ectodermal dysplasia, dyskeratosis follicularis, pseudoxanthoma elasticum, neurofibromatosis, tuberous sclerosis, syndromes associated with immune defects, Rothmund Thomson syndrome, Birt-Hogg-Dubé syndrome, Cowden syndrome, and other rare syndromes with cutaneous involvement
Department of Dermatology, Odense	Patient Administrative System	Odense University Hospital Søndre Boulevard 29, 5000 Odense http://www.sdu.dk/om_sdu/institutter_centre/klinisk_institut/forskning/forskningsenheder/open/projekter/op_19+hereditaert+angiooedem+hae See also http://www.haei.org/?q=node/1005/28	Anette Bygum, Dermatologist specialist in genodermatoses Email [e-mail]	National site for diagnosis and treatment of HAE and acquired Cl inhibitor deficiency
Centre for Oral Health in Rare Diseases, Department of Maxillofacial Surgery, (Odontologisk Landsdels og Videncenter, Kaebekirurgisk afdeling), Aarhus	Patient Administrative System	Aarhus University Hospital, Nørrebrogade 44, Building 9D, 2nd floor, 8000 Aarhus C www.odontviden.auh.dk	Center Chief, Hans Gjørup Email [e-mail]	Center focusing on development and function of the stomatognathic system in children and adults with rare conditions/diseases, eg, ectodermal dysplasia, osteogenesis imperfecta, Ehlers-Danlos syndrome, congenital neuromuscular diseases, hereditary rickets, cleidocranial dysplasia, amelogenesis imperfecta, and dentinogenesis imperfecta
Centre for Rare Oral Diseases (Odontologisk Videncenter), Copenhagen		Odontologisk Videncenter, Rigshospitalet, 5811 Blegdamsvej 9, 2100 København Ø http://www.rigshospitalet.dk/menu/AFDELINGER/Hovedortocentret/Odontologisk+Videncenter/	Center Chief, Jette Daugaard-Jensen Email [e-mail]	Expertise in treatment of ectodermal dysplasia, tooth mineralization disturbances, and tooth eruption anomalies

Table 3 Examples of project-specific data sources established in relation to past research projects, eg, PhD dissertations

Genetic registry (Danish name)	Description	Registration start/end	Data administrator/contact	Other details
Danish Mole Register	Hydatidiform moles, >400 cases	Western Denmark, 1986 to present	Department of Clinical Genetics, Aarhus University Hospital/Lone Sunde Email [e-mail]
Katballe cohort (Katballe kohorten)	Cohort of all colorectal cancer (CRC) patients diagnosed in former counties Aarhus, Viborg, Ringkøbing, and Ribe, and relatives to these patients	1995–1998	Departments of Clinical Genetics and Clinical Epidemiology, Aarhus University Hospital Contact person, Charlotte Kvist Lautrup Email [e-mail]	1657 CRC patients of whom 1200 have filled in a questionnaire regarding number of relatives; more than 10,000 of the relatives have been identified; the database contains information regarding self-reported and verified CRC
FHH and PHPT cohort (FHH/PHPT kohorten)	Familial hypocalciuric hyperecalcaemia (FHH) and primary hyperparathyrodism (PHPT)		Aarhus University Hospital, Signe Engkjær Christensen	66 FHH patients; 147 PHPT patients References: Christensen et al^Citation52 Christensen et al^Citation53
Borberg NF1 cohort (Borberg kohorten)	212 Danish patients with Neurofibromatosis 1 (NF1)	1924–1944; updated in 1986	Institute for Cellular and Molecular Genetics, Panum Institute, University of Copenhagen Contact person, Sven Asger Sørensen Email [e-mail]	76 NF1 probands References: Borberg^Citation38 Sørensen et al^Citation35
XLHED cohort (XLHED kohorten)	X-linked hypohidrotic ectodermal dysplasia	2007; updated 2012	Department of Clinical Genetics, Aarhus University Hospital, Contact person, Mary Nguyen Nielsen Email [e-mail]	91 molecularly confirmed XLHED cases; 146 registered HED cases References: Lexner et al^Citation54 Nguyen-Nielsen et al^Citation42

Abbreviations: XLHED, X-linked hypohidrotic ectodermal dysplasia; FHH, familial hypocalcuric hypercalcemia; NF1, neurofibromatosis 1; PHPT, primary hyperparathyroidism; CRC, colorectal cancer.

Table 4 Supplemental registries for data linkage and collection of medical histories

Genetic registry (Danish name)	Description	Registration start/end	Data administrator/contact	Other details
Danish National Registry of Patients^Citation43 (Landspatient registeret)	Nationwide registration of all hospital admissions, diagnoses, and outpatient contacts	1977 to present, since 1995 includes contacts to emergency rooms and outpatient clinics	State Serum Institute http://www.sst.dk/lndberetning%20og%20statistik/Landspatientregisteret.aspx	Diagnoses registered with ICD-8 from 1977 to 1993 and the ICD-10 from 1994 to present
Civil Registration System^Citation5,Citation41 (Det Centrale Personregister)	Administrative registry of all persons with legal residence in Denmark	April 2, 1968 to present	The Central Office of Civil Registration, Copenhagen http://www.cpr.dk/cpr/site.aspx?p=194&ArticlelD=4327	Variables include the personal identification number of parents and their children, date of birth, gender, vital status, marital status, profession, place of birth, and others
Danish Cancer Registry^Citation15,Citation17 (Cancerregisteret)	Registration of all incident solid tumor cancers	1943 to present; mandatory reporting since 1987	State Serum Institute http://www.ssi.dk/Sundhedsdataogit/Registre/Cancerregisteret.aspx	From 1943 to 2003 tumors were classified with ICD-7; since 1994, classification with ICD-10
Danish Medical Birth Registry^Citation32 (Fødselsregisteret)	Peripartum data on all children born in Denmark	1973 to present (electronic reporting directly to DNRP since 1995)	State Serum Institute http://www.ssi.dk/Sundhedsdataogit/Registre/Fodselsregister.aspx	Variables include gender, birth weight, gestational age, birth length, Apgar score, and maternal variables such as parity, smoking status during pregnancy, and others
National Registry of Congenital Abnormalities^Citation29,Citation30 (Misdannelsesregistret)	Congenital malformations detected during first year of life, stillborn with congenital malformations and late miscarriages (> 12 gestational weeks)	1983 to present (electronic reporting directly to DNRP since 1995)	State Serum Institute http://www.ssi.dk/Sundhedsdataogit/Registre/Misdannelsesregister.aspx	Diagnoses of congenital malformations, which were specified by the Danish Health and Medicines Authority. More specific and detailed than the ICD-diagnosis codes
National Fetal Medicine Database^Citation33 (National Føtalmedicinsk Database; FØTOdatabasen)	Prenatal ultrasound examinations	January 1, 2006 to present, nationwide since 2008	Center for Fetal Medicine and Pregnancy, Department of Obstetrics, Rigshospitalet, Copenhagen Contact person, Ann Tabor Email [e-mail] http://www.dfms.dk/foetodata.shtml	Over 260,000 prenatal registrations, eg, first trimester ultrasound scans and biomarker diagnostics; second trimester malformation scans with ICD-10 registration of congenital malformations; linked to the DCCR (for data on perinatal chromosomal analyses), DNRP, and DMBR
Danish Twin Registry^Citation55 (Det Danske Tvillingregister)	Multiple pregnancies	1870 to 2008, nationwide	National Institute of Public Health, University of Southern Denmark, Odense Email [e-mail] http://www.sdu.dk/en/Om_SDU/Institutter_centre/1st_sundhedstjenesteforsk/Centre/DTR	>80,000 twin pairs registered. Variables include pedigree data from church books and Civil Registration System registry; data on lifestyle, cause of death, patient questionnaires, clinical examinations, and interviews
Danish Cerebral Palsy Registry^Citation56 (Cerebral Parese Registret)	Cerebral palsy	1965 to present, nationwide since 1995	National Institute of Public Health, University of Southern Denmark, Odense http://www.si-folkesundhed.dk/Forskning/Generelt%20om%20forskning/Registre%20og%20follow-up%20studier/Cerebral%20Parese%20Registret.aspx	Variables include type and severity, type of functional handicaps, treatment, data on mother and case pertaining to pregnancy, birth, and postnatal period
SCOR Database^Citation40 (Sundhedsstyrelsens Centrale Odontologiske Register)	Children’s dental health status	1972 to present, nationwide	Danish Health and Medicines Authority http://www.sst.dk/publ/publ1999/indb_tandpleje/indhold.html	Variables include teeth eruptions, missing teeth, and caries status
Danish National Pathology Registry^Citation44 (Patobank)	Reports of all pathological examinations conducted in Denmark	1997 to present	Danish Health and Medicines Authority http://www.sst.dk/publ/Publ2011/DOKU/FaellesindhBasregPatoAnatUs.pdf and http://www.patobank.dk/	Includes some incomplete data prior to 1997
Danish Newborn Screening Biobank and Registry^Citation6 (Den Neonatale Screenings Biobank/Phenylketonuria biobank)	Phenylketonuria	1982 to present, nationwide	State Serum Institute Contact person; David Haugaard www.ssi.dk See also the Danish National Biobank http://www.biobankdenmark.dk/The%20Biobank%20Register/More%20about%20Biobank%20Register.aspx	Approximately 1.9 million neonatal blood samples to date

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