Screening for the IDDM high-risk genotype. A rapid microtitre plate method using serum as source of DNA.
Norwegian babies born with the HLA-DRB1*0401-DQA1*03-DQB1*0302/DRB1*03-DQA1+ ++*05-DQB1*0201 genotype have an estimated 17% lifetime risk of developing insulin-dependent diabetes mellitus (IDDM). Identifying these children is important for future prevention, and for studies of the non-genetic factors involved in IDDM. The aim of the study was to develop a rapid screening method for this high-risk genotype. DNA was extracted from serum collected during routine newborn screening for phenylketonuria and hypothyreosis. The second exons of HLA-DQA1 and DQB1 were co-amplified using biotinylated primers, amplicons were hybridized to a set of seven probes immobilized on a microtitre plate using a single hybridisation temperature, and detected colorimetrically by streptavidin-HRP conjugate and tetramethylbenzidine substrate. The DRB1*04 subtyping was performed using six different probes at identical conditions. The prevalence of the DRB1*0401-DQA1*03-DQB1*0302/DRB1*03-DQA1*0 5-DQB1*0201 genotype among 1,026 Norwegian babies was 2.7% (CI 95%: 1.7-3.7%). The new high-throughput genetic screening method for IDDM risk can easily be automated and included in newborn screening programs.
Cinek
O
O
National Institute of Public Health, Section of Epidmiology, Oslo, Norway.
Wilkinson
E
E
Paltiel
L
L
Saugstad
O D
OD
Magnus
P
P
Rønningen
K S
KS
D000483:Alleles; D004247:DNA / Q000097:blood / Q000235:genetics; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000453:epidemiology / Q000209:etiology / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D005820:Genetic Testing / Q000379:methods; D006681:HLA-D Antigens / Q000235:genetics*; D006801:Humans; D007231:Infant, Newborn; D009664:Norway; D012307:Risk Factors; D017422:Sequence Analysis, DNA / Q000379:methods
D006681:HLA-D Antigens; D004247:DNA