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2022 MAR 3 (NewsRx) -- By a News Reporter-Staff News Editor at Women's Health Weekly -- New research on Oncology - Ovarian Cancer is the subject of a report. According [...]

2022 FEB 24 (NewsRx) -- By a News Reporter-Staff News Editor at Women's Health Weekly -- Researchers detail new data in Biotechnology - Cancer Gene Therapy. According to news originating [...]

Hepatic nuclear factor-4α (HNF-4α), a transcription factor involved in the regulation of serum lipid and glucose levels, has recently been associated with type 2 diabetes. The HNF-4α gene (HNF4A) resides on chromosome 20q12-q13.1, which, in addition to type 2 diabetes, has also previously been linked to high triglycerides in Finnish familial combined hyperlipidemia (FCHL) families. FCHL, characterized by elevated levels of serum total cholesterol, triglycerides, or both, is a common dyslipidemia observed in up to 20% of patients with premature coronary heart disease. Considering the clear phenotypic overlap between type 2 diabetes and FCHL, both predisposing to high serum triglycerides and glucose intolerance, we tested this gene for association in dyslipidemic families originating from two distinct populations, Finnish and Mexican, and comprising 1,447 subjects. Our data show that common HNF4A variants and haplotypes are associated with elevated serum lipid levels and the metabolic syndrome (P = 0.008-0.04), as well as with elevated glucose parameters (P = 0.008-0.03), using family-based association analysis. Importantly, both Finnish and Mexican families shared two common lipid-associated HNF4A haplotypes (P = 0.005 for total cholesterol and 0.006 for triglycerides). In conclusion, we show for the first time that common HNF4A variants are associated with high serum lipid levels and the metabolic syndrome., Recently, a number of independent groups identified associations between single nucleotide polymorphisms (SNPs) in the hepatic nuclear factor-4α (HNF-4α) gene HNF4A on 20q12-q13.1 and type 2 diabetes in several populations [...]

Recently, various subtypes of familial hyperinsulinemic hypoglycemia with an autosomal-dominant inheritance have been etiologically characterized. In the present study, we have delineated the genetics and metabolic phenotype of a novel form of hypoglycemia in a large pedigree with an apparent autosomal-dominant transmission. After initial investigations of the proband, her mother, and a sister, the study was extended to 19 family members in three generations. Glucose tolerance was assessed by a 5-h oral glucose tolerance test (OGTT) and insulin sensitivity by euglycemic-hyperinsulinemic clamp in six affected family members and six control subjects. To identify the genetic cause of hypoglycemia, linkage analysis and mutation analysis of genomic DNA from all family members were performed. All affected family members were characterized by postprandial hypoglycemia, fasting hyperinsulinemia, and an elevated serum insulin-to-C-peptide ratio. The 5-h OGTT demonstrated hyperinsulinemic hypoglycemia, and the clamp studies showed reduced insulin sensitivity and clearance of serum insulin in affected family members compared with control subjects. Linkage analysis and subsequent mutation screening revealed a missense mutation (Arg1174Gln) in the tyrosine kinase domain of the insulin receptor gene that cosegregated with the disease phenotype (logarithm of odds [LOD] score 3.21). In conclusion, we report a novel syndrome of autosomal-dominant hyperinsulinemic hypoglycemia. The findings demonstrate the coexistence of severe postprandial hypoglycemia, insulin resistance, and impaired insulin clearance and suggest that hypoglycemia should be considered as a phenotype linked to heterozygote mutations in the insulin receptor gene., Until recently, familial persistent hyperinsulinemic hypoglycemia was considered a syndrome of early infancy with a recessive inheritance (1). In hundreds of cases, mutations in the β-cell sulfonylurea receptor (SUR1) gene [...]

Here we report the first cloned N-ethyl-nitrosourea (ENU)-derived mouse model of diabetes. GENA348 was identified through free-fed plasma glucose measurement, being more than 2 SDs above the population mean of a cohort of >1,201 male ENU mutant mice. The underlying gene was mapped to the maturity-onset diabetes of the young (MODY2) homology region of mouse chromosome 11 (logarithm of odds 6.0). Positional candidate gene analyses revealed an A to T transversion mutation in exon 9 of the glucokinase gene, resulting in an isoleucine to phenylalanine change at amino acid 366 (I366F). Heterozygous mutants have 67% of the enzyme activity of wild-type littermates (P < 0.0012). Homozygous mutants have less enzyme activity (14% of wild-type activity) and are even less glucose tolerant. The GENA348 allele is novel because no mouse or human diabetes studies have described a mutation in the corresponding amino acid position. It is also the first glucokinase missense mutation reported in mice and is homozygous viable, unlike the global knockout mutations. This work demonstrates that ENU mutagenesis screens can be used to generate models of complex phenotypes, such as type 2 diabetes, that are directly relevant to human disease., Type 2 diabetes is a heterogeneous metabolic disorder characterized by hyperglycemia resulting from defects in insulin action and/or insulin secretion. The underlying causes are both genetic and environmental (notably for [...]

Mutations in human insulin cause an autosomal-dominant syndrome of diabetes and fasting hyperinsulinemia. We demonstrate by residue-specific photo cross-linking that diabetes-associated mutations occur at receptor-binding sites. The studies use para-azido-phenylalanine, introduced at five sites by total protein synthesis. Because two such sites ([Val.sup.A3] and [Phe.sup.B24]) are largely buried in crystal structures of the free hormone, their participation in receptor binding is likely to require a conformational change to expose a hidden functional surface. Our results demonstrate that this surface spans both chains of the insulin molecule and includes sites of rare human mutations that cause diabetes., The insulinopathies describe a monogenic form of adult-onset diabetes due to mutations in the insulin gene (1,2). Patients respond normally to exogenous insulin but exhibit fasting mutant hyperinsulinemia due to [...]

OBJECTIVE--Mutations in the highly homologous transcription factors hepatocyte nuclear factor (HNF)-1α and -1β cause maturity-onset diabetes of the young types 3 and 5, respectively. Diabetes due to HNF-1α mutations is [...]

In 1878, Madelung described a painful, disabling, and deforming abnormality of the forearm in which misalignment of the bones of the wrist and forearm resulted in a spontaneous forward subluxation [...]

Hereditary hemochromatosis may lead to hepatic cirrhosis, cardiomyopathy, diabetes, arthritis, and impotence (1,2). In the Caucasian population, HFE gene mutations (C282Y and H63D) are present in the majority of patients [...]

The argument that there's a connection between type 1 diabetes and viruses has gotten a little stronger. Researchers found four mutations in a human gene that seem to lower the [...]