Evidence for linkage on chromosome 4p16.1 in Type 1 diabetes Danish families and complete mutation scanning of the WFS1 (Wolframin) gene.
OBJECTIVE
To investigate whether the WFS1 gene, the gene for Wolfram syndrome, is a susceptibility gene for more common forms of diabetes in the Danish population.


METHODS
One hundred and fifty-two Danish Type 1 diabetes mellitus sib-pair families were genotyped for two microsatellite markers situated within 5 cM of the WFS1 gene and analysed for linkage and association using the sib-TDT. The entire coding region, the 5'UTR and 3'UTR of the WFS1 gene, were screened for mutations by direct sequencing in 29 selected Type 1 diabetes patients. Four of the identified mutations were tested for linkage and association in 255 Danish Type 1 diabetes families (including 103 simplex families).


RESULTS
Evidence for linkage to Type 1 diabetes was found as the second most frequent allele of the marker D4S394 were transmitted 137 times (T = 61%) and not transmitted 88 times to affected offspring (Puc = 0.0011). Twelve mutations were found in the coding region and three mutations in the 3'UTR. No evidence for linkage and association to Type 1 diabetes was found testing four of the identified amino acid substitutions.


CONCLUSIONS
Evidence of linkage to Type 1 diabetes was observed in the Danish family collection. However, no evidence of linkage and association was observed for any of the analysed polymorphisms, suggesting that other variations must be responsible for the observed evidence of linkage in the region.
Steno Diabetes Centre, Gentofte, Denmark.
Z M
ZM
Larsen
J
J
Johannesen
O P
OP
Kristiansen
J
J
Nerup
F
F
Pociot
D017668:Age of Onset; D000483:Alleles; D002894:Chromosomes, Human, Pair 4 / Q000235:genetics*; D003718:Denmark; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics*; D005192:Family Health; D008040:Genetic Linkage / Q000235:genetics*; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005820:Genetic Testing / Q000379:methods; D005838:Genotype; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics*; D018895:Microsatellite Repeats / Q000235:genetics; D009154:Mutation / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D020641:Polymorphism, Single Nucleotide / Q000235:genetics
D005819:Genetic Markers; D008565:Membrane Proteins; C114987:wolframin protein