E. Imano et al., RAPID SCREENING METHOD OF ABNORMAL INSULIN-RECEPTOR GENE-EXPRESSION -ALLELE-SPECIFIC OLIGONUCLEOTIDE HYBRIDIZATION BY USING SILENT POLYMORPHISMS, Biochimica et biophysica acta, 1181(2), 1993, pp. 131-134
An asymmetrical reduction in the levels of the insulin receptor mRNA t
ranscribed from one allele was reported in some patients with severe i
nsulin resistance and non-insulin-dependent diabetes mellitus (NIDDM).
To detect this abnormality, we designed the less laborious method;All
ele-specific oligonucleotide hybridization of the amplified mRNA (cDNA
) by using silent polymorphisms in the insulin receptor gene (nucleoti
de positions at 1686 and 1698). The allelic frequencies of C-1686 and
T-1686 were 0.63 and 0.37, respectively (0.60 and 0.40 in 10 normal su
bjects, and 0.67 and 0.33 in 20 NIDDMs; n.s.). Similarly, the allelic
frequencies of A-1698 and G-1698 were 0.47 and 0.53, respectively (0.5
0 and 0.50 in the normal subjects, and 0.45 and 0.55 in the NIDDMs; n.
s.). These results suggest that these two polymorphisms are very commo
n in Japanese. Nineteen (64%) out of 30 cases are heterozygous at one
or two position(s), suggesting that it is possible to distinguish the
mRNA transcribed from each of two alleles of the insulin receptor gene
with using allele-specific oligonucleotide hybridization. Although we
successfully measured the ratio of mRNA expression from two alleles o
f the gene in 20 NIDDMs, there was no patient whose mRNA transcribed f
rom one allele of the insulin receptor gene was extremely decreased. W
e showed that allele-specific oligonucleotide hybridization method is
useful for the screening of abnormal insulin-receptor gene expression.