ABSTRACT
INTRODUCTION: Gastric cancer is the most frequent gastrointestinal malignancy in Mexico and the proportion of patients younger than 40 years is one of the highest reported in the world literature. Recently several families with familial diffuse gastric cancer have been identified at the National Institute of Medical Sciences and Nutrition. Germline mutations in the E-cadherin gene (CHD1) have been described that result in the development of diffuse hereditary gastric cancer in young patients. METHODS: The complete coding sequence at exons 1 to 16 and the promoter region of CDH1 was amplified by polymerase chain reaction in peripheral blood samples of two patients with early onset familial diffuse gastric cancer. RESULTS: No germline inactivating mutations of CHD1 were found on either patient. Single nucleotide polymorphisms -160 C->A were detected in the promoter region of CDH1 in both patients. CONCLUSIONS: The polymorphism -160 C->A theoretically confers an increased risk of developing diffuse gastric cancer. The relatives of these patients may an increased risk of gastric cancer among other tumors. There is presently not enough evidence to consider the -160 C->A polymorphism an etiologic factor of diffuse gastric cancer in these patients since the frequency and type of genetic alterations of CDH1 are largely unknown in the Mexican population. It will be necessary to conduct epidemiologic studies in the Mexican population to determine the influence that genetic alterations have on the genesis of diffuse gastric carcinoma.
Subject(s)
Cadherins/genetics , Stomach Neoplasms/genetics , Adult , Female , Humans , Male , Pedigree , Polymorphism, Single Nucleotide , Promoter Regions, GeneticABSTRACT
BACKGROUND: Recent data have supported an autoimmune etiology of vitiligo. Genetic factors also seem to play an important role in this disorder. The purpose of this study was to determine the presence and frequency of organ-specific autoantibodies in vitiligo patients and their relatives. METHODS: Twenty patients with vitiligo and two first or second degree relatives of each patient were interviewed and their sera analyzed for the presence of antithyroglobulin (ATg), antithyroid microsomal (ATM), antiparietal cell (APC), and antiadrenal (AAd) autoantibodies. The sera of 20 normal patients were used as control. RESULTS: A significantly increased frequency of ATg, ATM, and APC antibodies was found in vitiligo patients when compared to normal controls. First and second degree relatives had significantly increased frequencies of ATg and ATM. A high incidence of autoimmune/endocrine diseases was found in the patients' relatives, including a 25% prevalence of vitiligo. CONCLUSIONS: These findings not only support an autoimmune etiology for vitiligo, but also highlight the strong genetic contribution to this pigmentary disorder.
Subject(s)
Autoantibodies/blood , Vitiligo/immunology , Adolescent , Adrenal Glands/immunology , Adult , Autoimmune Diseases/genetics , Child , Endocrine System Diseases/genetics , Female , Humans , Male , Microsomes/immunology , Middle Aged , Organ Specificity , Parietal Cells, Gastric/immunology , Thyroglobulin/blood , Thyroglobulin/immunology , Thyroid Gland/immunology , Vitiligo/geneticsABSTRACT
Bullous pemphigoid has been reported in multiple publications to be associated with malignant neoplasms of different internal organ systems. This relationship was studied among forty patients seen at the Dermatology Clinics of the Puerto Rico Medical Center. The study demonstrated that Puerto Rican patients with bullous pemphigoid do not show an increased incidence of internal malignancy when compared with the general population matched for age, sex and study period. We conclude that extensive diagnostic studies for malignant neoplasms should not be the standard of care in patients with bullous pemphigoid. Additional studies should be guided by the clinical history and physical findings.
