Diabetes, Vol 45, Issue 2 267-269, Copyright © 1996 by American Diabetes Association
Identification of microsatellite markers near the human genes encoding the beta-cell ATP-sensitive K+ channel and linkage studies with NIDDM in Japanese
N Iwasaki, M Kawamura, K Yamagata, NJ Cox, S Karibe, H Ohgawara, N Inagaki, S Seino, GI Bell and Y Omori
Diabetes Center, Tokyo Women's Medical College, Japan.
ATP-sensitive K+ (KATP) channels play a key role in stimulus-secretion
coupling in pancreatic beta-cells. Recent studies have shown that the
beta-cell KATP channel comprises two subunits: a novel member of the
inwardly rectifying K+ channel family, designated BIR and expressed at
highest levels in pancreatic islets, and the sulfonylurea receptor (SUR).
Moreover, the genes encoding these two proteins are adjacent to one another
on human chromosome 11. Genetic factors contribute to the development of
NIDDM, and it seems likely that mutations in genes encoding proteins
involved in insulin secretion or action may contribute to NIDDM
susceptibility. The present study examined the contribution of the linked
BIR and SUR genes to the development of NIDDM. These genes were localized
to the same yeast artificial chromosome as two microsatellite DNA
polymorphisms, D11S902 and D11S921. These microsatellite DNA polymorphisms
were typed in 140 Japanese NIDDM-affected sib pairs. There was no evidence
for linkage between these markers and NIDDM, suggesting that genetic
variation in the BIR and SUR genes does not play a major role in
susceptibility to NIDDM in Japanese.