| Revista: | Salud mental |
| Base de datos: | PERIÓDICA |
| Número de sistema: | 000316783 |
| ISSN: | 0185-3325 |
| Autores: | González Ramírez, Adriana1 Díaz Martínez, Alejandro2 Díaz Anzaldúa, Adriana |
| Instituciones: | 1Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Departamento de Genética, México, Distrito Federal. México 2Universidad Nacional Autónoma de México, Facultad de Medicina, México, Distrito Federal. México |
| Año: | 2008 |
| Periodo: | May-Jun |
| Volumen: | 31 |
| Número: | 3 |
| Paginación: | 229-237 |
| País: | México |
| Idioma: | Español |
| Tipo de documento: | Revisión bibliográfica |
| Enfoque: | Analítico |
| Resumen en español | afectan la secuencia del ADN, por modificaciones que tienen lugar principalmente en las citosinas de éste y en las histonas de la cromatina. Se ha determinado que las modificaciones epigenéticas son mucho más frecuentes que aquellas que modifican la secuencia del ADN, por lo que constituyen uno de los fundamentos de la diversidad biológica, muestran la manera en que el ambiente puede modular la expresión genética y contribuyen así a nuestro fenotipo. Esta revisión reúne datos sobre la posible relevancia de la epigenética en el estudio de los trastornos mentales y como posible explicación parcial de las diferencias observadas entre gemelos «idénticos». Un conocimiento más profundo de los patrones epigenéticos podría contribuir a identificar factores de riesgo para estos trastornos |
| Resumen en inglés | monozygotic twin can develop an inherited disorder while his or her co-twin will always be disease-free. In addition to differences in susceptibility to inherited diseases, this kind of twins can display dissimilarities in somatic cell mutations (more overtly noticeable when ageing), their set of antibodies and T cell receptors, their number of mitochondrial DNA molecules, and chromosome X inactivation patterns in women, all of which are the main subject of many ongoing studies. A recent report shows that from 160 monozygotic twin pairs who were 3 to 74 years old, epigenetic patterns were identical early in life, but differences were more obvious at older ages, especially if twins were raised apart or if they had different medical history. Medical conditions, but also environmental factors such as pregnancy tobacco exposure, physical activity, and diet could contribute to differences in epigenetic patterns. It has been shown that epigenetic modifications (or epi-mutations) are more frequent than the ones that modify DNA sequence, so they are part of the fundamental causes of biological diversity, and they show how environment can modulate gene expression and contribute to our phenotype. Even when twin studies are sometimes considered purely genetic, they also give information about the influence of environmental factors. However, it is important to consider with caution the results from this type of studies. Heritability estimates are not unchangeable facts. They depend on the sample being analyzed, the genes involved in the specific sample, the characteristics of the environmental factors which members of this group were exposed to, and the precise moment the study was done. Epigenetics refers to changes that do not alter the DNA sequence but affect gene function due to chemical modifications which mainly occur in DNA cytosines and in chromatin-related histones |
| Disciplinas: | Medicina |
| Palabras clave: | Psiquiatría, Genética, Epigénesis, Heredabilidad, Trastornos mentales, ADN, Gemelos |
| Keyword: | Medicine, Psychiatry, Epigenesis, Heritability, Mental disorders, DNA, Twins, Genetics |
| Texto completo: | Texto completo (Ver PDF) |
