Genetic factors and clinical significance of acanthosis nigricans in obese Japanese children and adolescents.

Aim: To clarify the clinical significance of acanthosis nigricans (AN) and the association of gene polymorphisms in the ss2- and ss3-adrenergic receptors (B2ADR and B3ADR) in Japanese obese children and adolescents.

Methods: Seventy obese subjects (56 boys, 14 girls) from 5 to 19 y of age were examined as to clinical features. Genetic analyses were performed in 83 obese subjects (61 boys, 22 girls), 2 to 17 y of age.

Association of HLA-DR, -DQ genotype and CTLA-4 gene polymorphism with Graves' disease in Japanese children.

Objective: Childhood onset Graves' disease (GD) has been documented to be clinically distinct from adult onset GD, and an association with the genes encoding HLA and CTLA-4 (cytotoxic T lymphocyte antigen-4) has been reported in both Caucasian and Japanese adult GD patients. The aim of this study was to determine whether HLA-DR, -DQ and CTLA-4 are associated with childhood onset GD in Japanese individuals.

Methods: We investigated the genotype of HLA class II (DRB1, DQB1) and the A/G transition polymorphism of CTLA-4 exon 1 position 49 in 43 GD patients and in healthy controls for comparison.

Absence of Heterozygous K83E and R257X Mutations of the AIRE-1 Gene in 46 Children with Type 1 Diabetes and 44 Children with Graves' Disease.

Type 1 diabetes mellitus (DM) and Graves' disease are autoimmune diseases, and a number of genetic factors, including HLA and CTLA-4 genes, have been reported to contribute to their etiology. The gene responsible for autoimmune polyendocrinopathy- candidiasis-ectodermal dystrophy (APECED) has been cloned and named the autoimmune regulator-1 (AIRE-1) gene. AIRE-1 protein is thought to be a transcription regulatory protein and to have a role in the maintenance of immunological tolerance.

Fasting plasma ghrelin levels are negatively correlated with insulin resistance and PAI-1, but not with leptin, in obese children and adolescents.

Ghrelin is a novel growth hormone-releasing peptide isolated from human and rat stomach that induces weight gain by increasing food intake and reducing fat utilization. Although recent data indicate that ghrelin is downregulated in human adult obesity, the characteristics of human obesity are heterogeneous, especially in children and adolescents, and depend on the distribution of subcutaneous and visceral fat tissue. We measured fasting plasma ghrelin concentrations by radioimmunoassay in 49 obese Japanese children and adolescents (38 boys and 11 girls; mean age 10.

Impact of polymorphisms of human beta-adrenergic receptor gene on changes in height during growth hormone treatment.

The aim of this study was to investigate the occurrence of polymorphisms of the beta-adrenergic receptor gene in short children and to evaluate the possible influence of the polymorphisms on changes in height and obesity index in response to GH treatment. Of the 75 children enrolled in the study, 40 completed at least 5 years of GH treatment. The genotype distribution of the beta2 and 3-adrenergic receptor polymorphisms in the study population did not differ significantly from those reported in non-obese subjects.