Name: gene interaction maps in epistasis
Uploaded: 2023-04-30T10:14:33.000Z
Duration: 1 min 9 s
Channel: JoVE

Una relación contraria entre dos genes es la epistasis, donde un gen enmascara o altera la expresión de otro. Se dice que el gen que influye es epistático al gen que se está enmascarando.
Por ejemplo, un gen que codifica la proteína 1 relacionada con la tirosinasa, o TYRP1, determina el color del pelaje de los perros: negro o marrón.
Otro gen, Tyr, codifica la enzima tirosinasa, que es responsable de la pigmentación en los animales. Una mutación en este gen puede causar la ausencia de pigmento, lo que da como resultado un perro albino que carece de coloración.
El orden en el que se expresan estos dos genes se puede determinar mediante una prueba de epistasis.
Si una mutación en el gen Tyr produce un perro albino que todavía tiene el gen TYRP1 de tipo salvaje, se puede concluir que el gen Tyr enmascara el efecto del gen TYRP1. Esto significaría que Tyr es epistático a TYRP1.

<ol>
	<li>Michels, C.A. (2002). Análisis de Epistasis. En Técnicas genéticas para la investigación biológica, C.A. Michels (ed.). https://doi.org/10.1002/0470846623.ch6</li>
	<li>Bernstein, Harris, Henry C. Byerly, Frederic A. Hopf y Richard E. Michod. "Daño genético, mutación y la evolución del sexo". Ciencia 229, no. 4719 (1985): 1277-1281.</li>
</ol>

análisis de epistasis

Epistasis Analysis

Aunque Mendel eligió siete rasgos no relacionados en guisantes para estudiar la segregación genética, la mayoría de los rasgos implican múltiples interacciones genéticas que crean un espectro de fenotipos. Cuando la interacción de varios genes o alelos en diferentes ubicaciones influye en un fenotipo, esto se denomina epistasis. La epistasis a menudo implica que un gen enmascare o interfiera con la expresión de otro (epistasis antagonista). La epistasis ocurre a menudo cuando diferentes genes forman parte de la misma vía bioquímica. La expresión de un gen podría depender de un producto genético en la misma vía bioquímica.

Análisis epistático

El estudio de las interacciones epistáticas permite a los investigadores determinar la relación funcional entre genes, el orden de los genes en una vía y cómo los diferentes alelos impactan cuantitativamente en los fenotipos. Consideremos una reacción bioquímica catalizada por múltiples proteínas codificadas por diferentes genes. Los genes implicados en tales reacciones bioquímicas pueden enmascarar o inhibir otros genes implicados en la misma vía bioquímica, un fenómeno llamado epistasis. Se dice que estos genes pertenecen a un grupo de epistasis. Al analizar la relación epistática entre diferentes genes, los científicos pueden construir un mapa de orden de función que muestre la secuencia de eventos y genes involucrados en una vía. Este proceso se llama análisis epistático. Los alelos seleccionados para el análisis epistático deben tener fenotipos distintos.

Como tal, desde que se introdujo el concepto de epistasis, se ha vuelto cada vez más claro que la mayoría de los sistemas biológicos involucran muchos elementos genéticos que interactúan entre sí de maneras múltiples y complejas.

Análisis de epistasis

Aunque Mendel eligió siete rasgos no relacionados en los guisantes para estudiar la segregación de genes, la mayoría de los rasgos involucran múltiples interacciones de genes que crean un espectro de ...

Education

Educación

JoVE Core

Molecular Biology

Biología Molecular

Unit 2

Unidad 2

Analyzing Gene Expression and Function

Análisis de la expresión y función génica

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

gene interaction maps in epistasis

Gene interaction maps in epistasis show how different genes work together to shape a phenotype. In epistasis, the interaction of genes or alleles at different locations affects the final trait. This often happens when one gene masks or interferes with the expression of another gene.

Epistasis is common when genes are part of the same biochemical pathway. In that case, the expression of one gene can depend on a gene product made earlier in the pathway. Genes that mask or inhibit other genes in the same pathway are considered part of one epistasis group.

Epistatic analysis uses these interactions to reveal how genes are related. Scientists can use it to identify the functional relationship between genes, determine the order of genes in a pathway, and see how different alleles affect phenotypes in a quantitative way. When multiple proteins encoded by different genes take part in a biochemical reaction, epistatic analysis can help build an order-of-function map that shows the sequence of events and the genes involved.

To compare genes in this way, the alleles chosen for analysis must have distinct phenotypes. Since epistasis was first described, it has become clear that many biological systems include genetic elements that interact in complex ways. These interactions help explain why many traits do not follow simple single-gene patterns.

Gene Interaction Maps in Epistasis

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epistasis analysis

Gene interaction maps in epistasis show how different genes work together to shape a phenotype. In epistasis, the interaction of genes or alleles at different locations affects the final trait. This often happens when one gene masks or interferes with the expression of another gene. Epistasis is common when genes are part of the same biochemical pathway. In that case, the expression of one gene can depend on a gene product made earlier in the pathway. Genes that mask or inhibit other genes in...

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key terms and concepts

Explore how epistasis reveals gene interactions, pathway order, and phenotype changes through epistatic analysis in high school biology.

Gene Interaction Maps in Epistasis | JoVE K12

molecular biology

JoVE Core Biología Molecular presenta los procesos moleculares de la célula a través de lecciones claras y concisas de animaciones audiovisuales. Además, en los vídeos de científicos en acción, se muestran aplicaciones de estos conceptos mediante experimentos reales en laboratorios especializados.

Gene Interaction Maps in Epistasis

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