Caracterización del sistema polimórfico inserción/deleción del gen de la enzima convertidora de angiotensina en una muestra poblacional cubana / Characterization of the angiotensin-converting enzyme gene insertion/deletion polymorphism in a sample of Cuban population

Introducción: El polimorfismo de inserción/deleción del gen de la enzima convertidora de angiotensina es uno de los marcadores de predisposición a enfermedades más estudiados del eje renina-angiotensina. Los hallazgos contradictorios de estudios de su asociación con diversas afecciones hacen necesario tipificar previamente las poblaciones de interés. Objetivos: Caracterizar el comportamiento de este polimorfismo en los principales grupos raciales cubanos: caucasoide y negroide. Métodos: Mediante un método basado en la reacción en cadena de la polimerasa se genotipificaron 93 muestras de sangre periférica obtenidas de adultos aparentemente sanos (49 caucasoides y 44 negroides). Se calcularon las frecuencias alélicas y genotípicas grupales. Resultados: Los genotipos ID y DD predominaron en los grupos caucasoide y negroide, respectivamente. La comparación de las frecuencias genotípicas entre ambos grupos evidenció diferencias significativas para el genotipo ID. El alelo D resultó el más frecuente en las 2 subpoblaciones estudiadas. Ambas se encuentran en equilibrio de Hardy-Weinberg para este polimorfismo. Las comparaciones de las distribuciones alélicas y genotípicas entre los grupos y poblaciones foráneas similares, no arrojaron diferencias significativas. Conclusiones: Los resultados permiten considerar los valores de frecuencias genotípicas y alélicas obtenidos como referencia para posteriores estudios de asociación con enfermedades en la población cubana e indican la necesidad de tener en cuenta las características particulares de este polimorfismo en cada grupo racial

Introduction: The insertion/deletion polymorphism of the angiotensin-converting enzyme is one of the more studied markers of predisposition to diseases of the renin-angiotensin axis. The contradictory findings from the studies of its association with diverse affection make necessary to typify previously the interesting population. Objectives: To characterize the behavior of this polymorphism in the main Cuban racial groups: Caucasoid and Negroid. Methods: By means of the polymerase chain reaction-based on method the genotyping was made in 93 samples of peripheral blood obtained from adults apparently healthy (49 Caucasoid and 44 Negroid). The allelic and genotypical-group frequencies were estimated. Results: The ID and DD genotypes were predominant in the Caucasoid and Negroid, respectively. The comparison of the genotype frequencies among both groups showed significant differences for the ID genotype. The D allele was more frequent in the two study subpopulations. Both are in balance of Hardy-Weinberg for this polymorphism. The comparisons of the allelic and genotypical distributions among similar foreign populations and groups had not significant differences. Conclusions: Results allows us to consider the values of genotypical and allelic frequencies obtained as reference for further studies on the association with diseases in Cuban population and suggest the need of to take into account the own features of this polymorphism in each racial group

14-bp Insertion/Deletion Polymorphism of the HLA-G Gene in Osteosarcoma Patients

BACKGROUND: The major histocompatibility complex class I, G (human leukocyte antigen-G [HLA-G]) gene plays a vital role in the suppression of immune responses. Recently, a number of studies have reported an association between HLA-G and diseases (pregnancy complications, organ transplantation, and tumors). Some of the studies have revealed that the 14-bp insertion/deletion polymorphism might be associated with various diseases. The aim of the present study was to explore a possible influence of the 14-bp insertion/deletion polymorphism on osteosarcoma. METHODS: Genomic DNA was extracted from 75 formalin-fixed, paraffin-embedded tumor tissues derived from patients with conventional osteosarcoma (OSA) and 183 peripheral blood samples of healthy controls. Fifty-eight cases were South Korean patients with OSA and 17 cases were Argentine patients with OSA. The HLA-G 14-bp insertion/deletion polymorphism at exon 8 of the HLA-G locus was analyzed by polymerase chain reaction. RESULTS: There was a significantly different distribution profile for the 14-bp genotypes between the Korean OSA and Korean control groups. Specifically, there were more heterozygote 210 bp/224 bp genotypes in the Korean OSA group when compared to the Korean control group (62.1% vs 40.4%, p=0.002). CONCLUSIONS: The results suggest that HLA-G heterozygote patients may be more susceptible to OSA in the Korean population.

Angiotensin Converting Enzyme Insertion/Deletion Polymorphism in Korean Patients with Rheumatoid Vasculitis / 대한류마티스학회지

OBJECTIVE: Rheumatoid arthritis has various extra-articular manifestations including rheumatoid vasculitis. Angiotensin converting enzyme (ACE) gene shows insertion/deletion polymorphism and has II, ID, DD genotypes. ACE gene is related with vasoconstriction and endothelial dysfunction in cardiovascular disease. This study was undertaken to determine the association between ACE gene polymorphism and rheumatoid vasculitis. METHODS: Twenty-nine patients were collected as rheumatoid vasculitis group. DNA was isolated from blood samples collected from 114 Korean rheumatoid arthritis patients meeting American College of rheumatology 1987 revised criteria, and 114 healthy control group. Genotyping for the angiotensin converting enzyme gene insertion/deletion polymorphism was performed by polymerase chain reaction method. RESULTS: As vasculitis manifestation, 15 patients showed neuropathy, 13 showed scleritis, 3 showed skin rash. In rheumatoid vasculitis group, II, ID and DD polymorphism was seen in 8 (27.6%), 15 (51.7%), 6 (20.7%) patients respectively and 39 (34.2%), 57 (50.0%), and 18 (15.8%) in normal controls. There was no skewing of ACE I/D polymorphism in compared with normal group. In rheumatoid arthritis control group, II, ID and DD polymorphism was seen in 37 (32.5%), 64 (56.1%), and 13 (11.4%) patients. Among rheumatoid arthritis patient, there was no significant difference between patient with vasculitis and without vasculitis. CONCLUSION: Our results showed that genetic polymorphisms of angiotensin converting enzyme insertion/deletion gene has no association with the susceptibility to rheumatoid vasculitis.

The Effect of Angiotensin Converting Enzyme Gene Polymorphism in Children with Henoch-Schonlein Purpura Nephritis

PURPOSE: Henoch-Schonlein purpura(HSP) nephritis has been reported to vary from 25 to 50% among HSP patients and is a common cause of chronic glomerulonephritis in children. In our study, we evaluated the distribution and the association of the Insertion/Deletion(I/D) polymorphism of angiotensin converting enzyme(ACE) gene with clinical manifestations, particularly proteinuria in children with HSP nephritis, compared with that in HSP. METHODS: ACE gene polymorphism was determined in children with HSP nephritis(n=33) and HSP(n=28) who were diagnosed in Busan Paik hospital from January 1996 to June 2001. The I/D polymorphism of ACE gene was determined by PCR amplication of genomic DNA. RESULTS: The ACE I/D genotype frequency was DD : 25%, ID : 50%, II : 25% in HSP and DD : 24 %, ID : 46%, II : 30% in HSP nephritis, there was no significant difference in the genotype and allele frequencies between two groups. When statistical analysis was done according to the presence of D allele, the amount of 24-hour urinary protein excretion and the incidence of moderate to heavy proteinuria(>500 mg/m2/day) at onset and last follow-up were higher in DD/ID genotype than in those in II genotype, but these differences were not statistically significant. CONCLUSION: We suggest a lack of association between I/D polymorphism of ACE gene and clinical manifestations in children with HSP nephritis. However, further follow-up studies based on a sufficient number of patients and long term follow up periods are necessary to confirm the role of I/D polymorphism of ACE gene in children with HSP nephritis.