title: HLA associated type 1 diabetes risk in children of Pakistani migrants to Norway.
abstract: Type 1 diabetes (T1D) results from poorly defined interaction between susceptibility genes and environmental factors. The objective was to investigate Human Leukocyte Antigens (HLA) associated T1D risk among Pakistani newborns in Norway based on what published globally. DNA samples from 189 newborns, whose parents were first generation migrants from Pakistan, were analyzed. The hypothesis was tested using high resolution HLA genotyping for the -DRB1 and -DQB1 loci and high/intermediate for the -DQA1 locus. We identified 28 different DRB1, 13 DQB1 and 9 DQA1 alleles. Of the 39 different haplotypes identified, only five have been reported to confer T1D susceptibility. Among these the DR3-DQ2 (DRB1*03:01:01-DQA1*05-DQB1*02:01:01) haplotype was found in 18.5% (n=70) of the newborns, and 18.6% (n=13) of these were homozygotes. A diverse range of HLA haplotypes were identified amongst an ethnically homogenous group of newborns, with only a small proportion associated with T1D risk. The incidence of T1D among immigrants form South/East Asia is the lowest in the Norwegian Type 1 Diabetes Registry. The few included so far, are children of first generation immigrants. If incidence of T1D rises in the Norwegian Pakistani childhood population, as observed in the UK, then environmental triggers rather than genetic susceptibility will be the explanation.
authors.affiliation: Division of Society Contact and Information, Norwegian Institute of Public Health, Oslo, Norway. Electronic address: trond.rasmussen@fhi.no.
authors.forename: Trond
authors.initials: T
authors.lastname: Rasmussen
authors.affiliation: Women and Children's Division, Oslo University Hospital, Rikshospitalet and Institute of Clinical Medicine, Medical Faculty, Oslo University, Oslo, Norway.
authors.forename: Soen Eng
authors.initials: SE
authors.lastname: Yap
authors.affiliation: Women and Children's Division, Oslo University Hospital, Rikshospitalet and Institute of Clinical Medicine, Medical Faculty, Oslo University, Oslo, Norway.
authors.forename: Babill
authors.initials: B
authors.lastname: Stray-Pedersen
authors.affiliation: Department of Medical Genetics, Oslo University Hospital, Ullevål, Oslo, Norway.
authors.forename: Hanne E
authors.initials: HE
authors.lastname: Akselsen
authors.affiliation: Paediatric Epidemiology Group, Centre for Epidemiology and Biostatistics, University of Leeds, Leeds, UK.
authors.forename: Patricia A
authors.initials: PA
authors.lastname: McKinney
authors.affiliation: Women and Children's Division, Department of Pediatric Research, Oslo University Hospital, Rikshospitalet, Oslo, Norway.
authors.forename: Kjersti S
authors.initials: KS
authors.lastname: Rønningen
mesh_terms: D000483:Alleles; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000208:ethnology* / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006680:HLA Antigens / Q000235:genetics*; D059866:HLA-DQ beta-Chains / Q000235:genetics; D059811:HLA-DRB1 Chains / Q000235:genetics; D006239:Haplotypes; D006720:Homozygote; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D009664:Norway / Q000453:epidemiology; D010154:Pakistan / Q000208:ethnology; D011247:Pregnancy; D012042:Registries
chemical_list: D006680:HLA Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D059811:HLA-DRB1 Chains