How does it differ from range of reaction and genetic environmental correlation?
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Science tells us that the interactions between genes and environment shape human development. Despite the misconception that genes are “set in stone,” research shows that early experiences can determine how genes are turned on and off — and even whether some are expressed at all. The healthy development of all organs, including the brain, depends on how much and when certain genes are activated to do certain tasks. The experiences that children have early in life, therefore, play a crucial role in the development of brain architecture. Ensuring that children have appropriate, growth-promoting early experiences is an investment in their ability to become healthy, productive members of society. Show
Experiences Affect How Genes Are ExpressedInside the nucleus of each cell in our bodies, we have chromosomes, which contain the code for characteristics that pass to the next generation. Within these chromosomes, specific segments of genetic code, known as genes, make up long, double-helix strands of DNA.
Children inherit approximately 23,000 genes from their parents, but not every gene does what it was designed to do. Experiences leave a chemical “signature” on genes that determines whether and how the genes are expressed. Collectively, those signatures are called the epigenome. The brain is particularly responsive to experiences and environments during early development. External experiences spark signals between neurons, which respond by producing proteins. These gene regulatory proteins head to the nucleus of the neural cell, where they either attract or repel enzymes that can attach them to the genes. Positive experiences, such as exposure to rich learning opportunities, and negative influences, such as malnutrition or environmental toxins, can change the chemistry that encodes genes in brain cells — a change that can be temporary or permanent. This process is called epigenetic modification. 
Adverse Early Experiences Can Have Lifelong ConsequencesEpigenetic “markers” control where and how much protein is made by a gene, effectively turning the gene “on” or “off.” Such epigenetic modification typically occurs in cells that comprise organ systems, thereby influencing how these structures develop and function. Therefore, experiences that change the epigenome early in life, when the specialized cells of organs such as the brain, heart, or kidneys are first developing, can have a powerful impact on physical and mental health for a lifetime. The fact that genes are vulnerable to modification in response to toxic stress, nutritional problems, and other negative influences underscores the importance of providing supportive and nurturing experiences for young children in the earliest years, when brain development is most rapid. From a policy perspective, it is in society’s interest to strengthen the foundations of healthy brain architecture in all young children to maximize the return on future investments in education, health, and workforce development. For more information: Early Experiences Can Alter Gene Expression and Affect Long-Term Development: Working Paper No. 10. In genetics, reaction range (also known as range of reaction) is when the phenotype (expressed characteristics) of an organism depends both on the organism's genetic characteristics (genotype) and the environment. For instance, two siblings raised together can have radically different IQs and natural talents. Because of genetic variations between the two siblings and how these variations interact with their environment a wide range of personality/achievement
possibilities can lead to an almost infinite range of phenotype possibilities for the individual siblings involved. This range of reactions to the combination of genetics and environment is at the crux of the "nature vs. nurture" debate. Reaction range is the spectrum of phenotypic possibilities that either of these siblings could end up with due to the interaction of their specific genes and the environment they are exposed to.
This is the classic argument of nature versus nurture. We know that both environment and genetics influence a person’s development in various ways, but does one outweigh the other in its influence? To understand the role heredity has on development, researchers use the heritability estimate, which measures the extent to which individual traits are due to genetics. The estimates are obtained from kinship studies, or twin studies, that compare characteristics of family members. The findings of these studies showed heredity having a moderate role in development, but playing an important role in personality characteristics. Most researchers have accepted that heredity and environment work together. A person’s range of reaction is their genetically determined, unique response to their environment and can be applied to any characteristic. Reaction ranges prove that because we are all genetically different, we may respond differently to the same environment. The concept of genetic-environmental correlation states that our genes influence the environments that we are exposed to. When children are younger, it is common to see passive correlation, meaning the child has no control. Parents provide their child’s environment, tying it to heredity. The other common correlation is evocative, meaning children’s responses are influenced by their heredity. Active correlation takes place as children get older and gain experiences beyond the family. When given the freedom to make their own choices, children tend to choose environments that complement their heredity, called niche-picking. The influence of heredity and environment changes with age, as genetic factors become more important in determining environment as people get older. Of course parents and other adults can give children experiences that alters the expression of their heredity. The relationship between heredity and genes is proving to be bidirectional, meaning genes affect people’s behavior and experiences, but their experiences and behavior also affect their genes. This view is called epigenetic framework, meaning development results from bidirectional, ongoing exchanges between heredity and all levels of environment. YouTube VideoHow does range of reactions explain the geneAccording to the concept of range of reaction, genes set definite limits on potential, and environment determines how much of that potential is achieved. Another perspective on the interaction between genes and the environment is the concept of genetic environmental correlation.
What is the difference between genetic and environmental factors?Your genes hold the basic instructions for your body to grow and function, but they are far from the only thing controlling your traits. Most traits are shaped both by a person's genes and by environmental factors. Environmental factors include everything outside of DNA that affects your traits.
What is the relationship between genetic and environmental factors?Science tells us that the interactions between genes and environment shape human development. Despite the misconception that genes are “set in stone,” research shows that early experiences can determine how genes are turned on and off — and even whether some are expressed at all.
What is a reactive gene correlation when considering genes and the environment?Evocative (or reactive) genotype–environment correlation refers to the association between an individual's genetically influenced behaviour and others' reactions to that behaviour.
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