Family association studies of markers on chromosome 2q and Type 1 diabetes in subjects from South India.
BACKGROUND
Several Type 1 diabetes susceptibility loci have been located to chromosome 2q12-21. However, results have not always been consistent and this may reflect study design and the population analysed. We have used a family-based design to look for an association between Type 1 diabetes and markers located to 2q12-21.


METHODS
Ninety-one South Indian families consisting of subjects with Type 1 diabetes and their parents were genotyped for eight polymorphic markers localised to 2q12-21, which includes the interleukin-1 gene cluster. Radiation hybrid mapping was used to localise the map position of D2S308 and D2S363 on 2q12-21. The extended transmission disequilibrium test was used for statistical analysis.


RESULTS
No associations were found between Type 1 diabetes and markers located in and around the interleukin-1 gene cluster or the interleukin-1 Type 1 receptor. In contrast, a suggestive association was found between Type 1 diabetes and two closely-linked markers telomeric of the interleukin-1 gene cluster (D2S308 and D2S363, separated by 3.3 cR) (p=0.004 and p=0.002, respectively).


CONCLUSIONS
This preliminary study suggests that a locus close to D2S308 and D2S363 is involved in the aetiology of Type 1 diabetes in the South Indian population.
Department of Diabetes and Metabolic Medicine and Department of Psychiatry, St Bartholomew's and The Royal London School of Medicine, London, UK.
W B
WB
Ogunkolade
A
A
Ramachandran
M F
MF
McDermott
T R
TR
Kumarajeewa
D
D
Curtis
C
C
Snehalatha
V
V
Mohan
P G
PG
Cassell
J
J
Eskdale
G
G
Gallagher
G A
GA
Hitman
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D002874:Chromosome Mapping; D002889:Chromosomes, Human, Pair 2; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics* / Q000276:immunology; D005260:Female; D005819:Genetic Markers; D006801:Humans; D007194:India; D007375:Interleukin-1 / Q000235:genetics*; D015810:Linkage Disequilibrium; D008297:Male; D005810:Multigene Family
D005819:Genetic Markers; D007375:Interleukin-1