TY - JOUR
T1 - A point mutation inactivating the sulfonylurea receptor causes the severe form of persistent hyperinsulinemic hypoglycemia of infancy in Finland
AU - Otonkoski, Timo
AU - Ämmälä, Carina
AU - Huopio, Hanna
AU - Cote, Gilbert J.
AU - Chapman, Joanna
AU - Cosgrove, Karen
AU - Ashfield, Rebecca
AU - Huang, Eileen
AU - Komulainen, Jorma
AU - Ashcroft, Frances M.
AU - Dunne, Mark J.
AU - Kere, Juha
AU - Thomas, Pamela M.
PY - 1999
Y1 - 1999
N2 - Mutations in genes encoding the ATP-regulated potassium (K(ATP)) channels of the pancreatic β-cell (SUR1 and Kir6.2) are the major known cause of persistent hyperinsulinemic hypoglycemia of infancy (PHHI). We collected all cases of PHHI diagnosed in Finland between 1983 and 1997 (n = 24). The overall incidence was 1:40,400, but in one area of Central Finland it was as high as 1:3,200. Haplotype analysis using polymorphic markers spanning the SUR1/Kir6.2 gene cluster confirmed linkage to the 11p region. Sequence analysis revealed a novel point mutation in exon 4 of SUR1, predicting a valine to aspartic acid change at amino acid 187 (V187D). Of the total cases, 15 affected individuals harbored this mutation in heterozygous or homozygous form, and all of these had severe hyperinsulinemia that responded poorly to medical treatment and required subtotal pancreatectomy. No K(ATP) channel activity was observed in β-cells isolated from a homozygous patient or after coexpression of recombinant Kir6.2 and SUR1 carrying the V187D mutation. Thus, the mutation produces a nonfunctional channel and, thereby, continuous insulin secretion. This unique SUR1 mutation explains the majority of PHHI cases in Finland and is strongly associated with a severe form of the disease. These findings provide diagnostic and prognostic utility for suspected PHHI patients.
AB - Mutations in genes encoding the ATP-regulated potassium (K(ATP)) channels of the pancreatic β-cell (SUR1 and Kir6.2) are the major known cause of persistent hyperinsulinemic hypoglycemia of infancy (PHHI). We collected all cases of PHHI diagnosed in Finland between 1983 and 1997 (n = 24). The overall incidence was 1:40,400, but in one area of Central Finland it was as high as 1:3,200. Haplotype analysis using polymorphic markers spanning the SUR1/Kir6.2 gene cluster confirmed linkage to the 11p region. Sequence analysis revealed a novel point mutation in exon 4 of SUR1, predicting a valine to aspartic acid change at amino acid 187 (V187D). Of the total cases, 15 affected individuals harbored this mutation in heterozygous or homozygous form, and all of these had severe hyperinsulinemia that responded poorly to medical treatment and required subtotal pancreatectomy. No K(ATP) channel activity was observed in β-cells isolated from a homozygous patient or after coexpression of recombinant Kir6.2 and SUR1 carrying the V187D mutation. Thus, the mutation produces a nonfunctional channel and, thereby, continuous insulin secretion. This unique SUR1 mutation explains the majority of PHHI cases in Finland and is strongly associated with a severe form of the disease. These findings provide diagnostic and prognostic utility for suspected PHHI patients.
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U2 - 10.2337/diabetes.48.2.408
DO - 10.2337/diabetes.48.2.408
M3 - Article
C2 - 10334322
AN - SCOPUS:0344629350
SN - 0012-1797
VL - 48
SP - 408
EP - 415
JO - Diabetes
JF - Diabetes
IS - 2
ER -