24 research outputs found
Nonsegmental Vitiligo and Autoimmune Mechanism
Nonsegmental vitiligo is a depigmented skin disorder showing acquired, progressive, and depigmented lesions of the skin, mucosa, and hair. It is believed to be caused mainly by the autoimmune loss of melanocytes from the involved areas. It is frequently associated with other autoimmune diseases, particularly autoimmune thyroid diseases including Hashimoto's thyroiditis and Graves' disease, rheumatoid arthritis, type 1 diabetes, psoriasis, pernicious anemia, systemic lupus erythematosus, Addison's disease, and alopecia areata. This indicates the presence of genetically determined susceptibility to not only vitiligo but also to other autoimmune disorders. Here, we summarize current understanding of autoimmune pathogenesis in non-segmental vitiligo
Linkage disequilibrium mapping of the gene for Hermansky-Pudlak syndrome to chromosome 10q23. 1-q23.3
Hermansky-Pudlak syndrome (HPS) is an autosomal recessive disorder characterized by the triad of tyrosinase-positive oculocutaneous albinism, bleeding diathesis due to storage-pool deficiency of platelets, and a lysosomal ceroid storage disease. The disorder is particularly frequent in Puerto Rico and in an isolated village in the Swiss Alps. We have used a linkage disequilibrium mapping approach to localize the HPS gene in both of these groups to a 0.6 centiMorgan interval in chromosome segment 10q23.1-q23.3. These results indicate that the Puerto Rican and Swiss forms of HPS are either allelic or that they result from mutations in very closely linked genes in this region. This region of distal chromosome 10q is syntenic to the region of mouse chromosome 19 that includes ‘pale ear' (ep) and ‘ruby-eye' (ru), which must be considered as potential murine homologues to human HP
Organization and Nucleotide Sequence of the Human Hermansky-Pudlak Syndrome (HPS) Gene
Hermansky-Pudlak syndrome (HPS) is an autosomal recessive disorder characterized by oculocutaneous albinism, bleeding tendency, and lysosomal ceroid storage disease, associated with defects of multiple cytoplasmic organelles-melanosomes, platelet-dense granules, and lysosomes. HPS is frequently fatal and is the most common single-gene disorder in Puerto Rico. We previously characterized the human HPS cDNA and identified pathologic mutations in the gene in patients with HPS. The HPS protein is a novel apparent transmembrane polypeptide that seems to be crucial for normal organellar development. Here we describe the structural organization, nucleotide sequence, and polymorphisms of the human HPS gene. The gene consists of 20 exons spanning about 30.5kb in chromosome segment l0q23.1-q23.3. One of the intervening sequences is a member of the novel, very rare class of so-called “AT-AC” introns, defined by highly atypical 5' and 3' splice site and branch site consensus sequences that provide novel targets for possible pathologic gene mutations. This information provides the basis for molecular analyses of patients with HPS and will greatly facilitate diagnosis and carrier detection of this severe disorder
Generalized Vitiligo Associated Autoimmune Diseases in Japanese Patients Their Families
Background: Generalized vitiligo is an acquired disorder in which depigmented macules result from the autoimmune loss of melanocytes from the involved regions of skin. Generalized vitiligo is frequently associated with other autoimmune diseases, particularly autoimmune thyroid diseases (Hashimoto's thyroiditis and Graves' disease), rheumatoid arthritis, adult-onset type 1 diabetes mellitus, psoriasis, pernicious anemia, systemic lupus erythematosus, and Addison's disease.
Methods: One hundred and thirty-three Japanese patients with generalized vitiligo were enrolled in this study to investigate the occurrence of autoimmune diseases in Japanese patients with generalized vitiligo and their families.
Results: Twenty-seven of the patients with generalized vitiligo (20.3%) had autoimmune diseases, particularly autoimmune thyroid disease (sixteen patients, 12%) and alopecia areata (seven patients, 5.3%). Thirty-five patients (26.3%) had a family history of generalized vitiligo and/or other autoimmune diseases. Familial generalized vitiligo was present in fifteen (11.3%), including four families with members affected by autoimmune disorders. Twenty (15.0%) had one or more family members with only autoimmune disorders.
Conclusions: Among Japanese vitiligo patients, there is a subgroup with strong evidence of genetically determined susceptibility to not only vitiligo, but also to autoimmune thyroid disease and other autoimmune disorders