Insulin resistance and glucose dysmetabolism in polycystic ovary syndrome (PCOS) are related with the polymorphisms in the genes encoding the insulin receptor substrate (IRS) proteins, especially Gly972Arg/Ala513Pro polymorphism being reported to be associated with type-2 diabetes and PCOS.
Correction to: Functional Polymorphism Located in the microRNA Binding Site of the Insulin Receptor (INSR) Gene Confers Risk for Type 2 Diabetes Mellitus in the Bangladeshi Population.
Differences in the ratio of RNA encoding two isoforms of the insulin receptor between control and NIDDM patients. The RNA variant without Exon 11 predominates in both groups.
We have recently examined the exons encoding the insulin receptor tyrosine kinase domain and GLUT 4 in 30 subjects with Type 2 (non-insulin-dependent) diabetes mellitus using a molecular scanning approach.
Lack of association between the insulin receptor substrates-1 Gly972Arg polymorphism and type-2 diabetes mellitus among Saudis from Eastern Saudi Arabia.
We therefore characterized restriction-fragment-length polymorphisms of the insulin-receptor gene with the restriction enzyme Rsa 1 in 242 Mexican Americans and non-Hispanic Whites with type II diabetes and 202 age-, sex-, and ethnicity-matched control subjects who participated in a population-based study in San Antonio.
The aim of our study was to investigate whether common polymorphisms in the genes regulating the early insulin signalling pathway (insulin; A-23T, insulin-like growth factor 1 receptor [IGF-1R]; GAG1013GAA, plasma cell membrane glycoprotein 1 [PC-1]; K121Q, insulin receptor substrate [IRS-1]; G972R, insulin receptor substrate 2 [IRS-2]; G1057D and phosphatidylinositol 3-kinase p85 alpha [PI3K]; M326I) affect the weight change and development of Type 2 diabetes in the Finnish Diabetes Prevention Study.
These data indicate that the region of the insulin receptor gene coding for the intracellular portion of the beta-subunit is highly polymorphic and that polymorphisms surrounding specific exons can be identified by denaturing gradient gel blotting, but there is no evidence that variation at this locus contributes to NIDDM susceptibility in most individuals.
This review will focus on the structural and functional heterogeneity of the insulin receptor, and will discuss the pathogenetic role of insulin receptor variant forms and polymorphisms in the development of the common form of type 2 diabetes.
Identification of a mutation in the insulin receptor gene in a patient with a moderate degree of insulin resistance associated with morbid obesity suggests that insulin receptor mutations may exist in patients with Type 2 (non-insulin-dependent) diabetes mellitus associated with a moderate degree of insulin resistance.
The G1057D polymorphism in insulin receptor substrate (IRS)-2 gene is associated with type 2 diabetes mellitus (T2DM) risk, but results in published literatures are controversial.
Although no significant association of restriction fragment length polymorphism with Type 2 diabetes was found in the present study, our results suggest that the restriction fragment length polymorphism in the human insulin receptor gene varies among ethnic groups, and that the restriction fragment length polymorphism linked to the human insulin receptor gene might be a useful marker for the linkage study of the genes located close to the human insulin receptor gene on chromosome 19.
To investigate the potential of the technique for screening many patients, the 5 exons that encode the tyrosine kinase domain of the insulin receptor were examined in 30 unrelated white subjects with non-insulin-dependent diabetes mellitus (NIDDM).
The analysis of the INSR locus revealed "protective" haplotypes, and it may be possible to use two of the INSR haplotypes as genetic markers to identify individuals having a very low probability of developing NIDDM regardless of the presence of other genes conferring susceptibility to this disorder.
Since the insulin receptor substrate-1 (IRS-1) is the major substrate of the insulin receptor tyrosine kinase and has been shown to activate phosphatidylinositol (PI) 3-kinase and promote GLUT4 translocation, the IRS-1 gene is a potential candidate for development of non-insulin-dependent diabetes mellitus (NIDDM).
Mutations in or near the insulin receptor gene are unlikely to be the major cause of inherited predisposition to NIDDM in Chinese pedigrees that are related in this study, not excluding the principal role in the other Chinese or populations, while the mutations/variations near or at the glucose transporter 2 gene locus might be something of the cause, which needs more data to be ascertained, of familial NIDDM in Chinese pedigrees.
We conclude that the association between the Met985 variant in the insulin receptor gene and type 2 diabetes, which we previously reported in the Rotterdam study, is supported by thejoint analysis with a second population-based study and other studies.
Each pedigree was initially examined with insulin receptor restriction fragment length polymorphisms to determine whether any allele segregated with Type 2 diabetes in these pedigrees.
The significance of insulin receptor gene variants in the aetiology of Type 2 (non-insulin-dependent) diabetes mellitus has been investigated by analysis of restriction fragment length polymorphisms in a genetically homogeneous Swedish population.
The peroxisome proliferator-activated receptor gamma (PPARG), Pro12Ala and the insulin receptor substrate (IRS1), Gly972Arg confer opposite effects on insulin resistance and type 2 diabetes mellitus (T2DM).