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Secuencias de genoma, epigenoma y ARN de gemelos monocigóticos discordantes para la esclerosis múltiple
Sergio E Baranzini1, Joann Mudge, Jennifer C van Velkinburgh
1Department of Neurology, University of California at San Francisco, San Francisco, California 94143, USA. sebaran@cgl.ucsf.edu
Nature
|April 30, 2010
Resumen
Los gemelos idénticos con esclerosis múltiple (EM) no mostraron diferencias genéticas o epigenéticas significativas, desafiando la idea de que los factores ambientales solos causan la discordancia de la enfermedad. Este estudio secuenció genomas y epigenomas gemelos para comprender la naturaleza frente a la crianza en la EM.
Área de la Ciencia:
- Genética La genética.
- Inmunología Inmunología.
- La neurociencia es la neurociencia.
Sus antecedentes:
- Los gemelos monocigóticos (idénticos) son cruciales para estudiar las influencias genéticas frente a las ambientales en enfermedades como la esclerosis múltiple (EM).
- La discordancia de la enfermedad de EM en gemelos idénticos tradicionalmente sugiere que los factores ambientales juegan un papel importante.
- Descubrimientos recientes indican posibles variaciones genéticas y epigenéticas entre gemelos idénticos, poniendo en duda este modelo.
Objetivo del estudio:
- Investigar las diferencias genéticas, epigenéticas y transcriptómicas en pares de gemelos monocigóticos discordantes para la esclerosis múltiple.
- Para determinar si tales diferencias pueden explicar la discordancia observada en el desarrollo de la EM entre gemelos idénticos.
Principales métodos:
- Secuenciación del genoma completo de un par de gemelos idénticos discordantes de MS.
- Secuenciación del transcriptoma de ARN y el epigenoma de linfocitos CD4 (((+) de tres pares de gemelos idénticos discordantes de EM.
- Análisis de polimorfismos de un solo nucleótido (SNPs), polimorfismos de inserción-deleción, haplotipos de HLA, variaciones en el número de copias y patrones de metilación del ADN.
Principales resultados:
- No se encontraron diferencias genéticas reproducibles (SNP, indels) entre los gemelos.
- No se observaron diferencias significativas en los haplotipos de HLA, los SNPs de susceptibilidad a la EM, las variaciones en el número de copias o la expresión génica.
- Se detectaron diferencias epigenéticas mínimas (metilación del ADN) entre gemelos, mucho menos que entre individuos no relacionados o tejidos diferentes.
Conclusiones:
- El estudio no encontró evidencia de diferencias genéticas, epigenéticas o transcriptómicas que expliquen la discordancia de la enfermedad de EM en gemelos idénticos.
- Estos hallazgos desafían la interpretación tradicional de los estudios de gemelos idénticos en la patogénesis de la EM.
- Esta investigación proporciona las primeras secuencias de genomas individuales femeninas, gemelas y enfermedades autoinmunes reportadas.
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