Contents
What happens when genes are duplicated?
Gene duplications are an essential source of genetic novelty that can lead to evolutionary innovation. Duplication creates genetic redundancy, where the second copy of the gene is often free from selective pressure—that is, mutations of it have no deleterious effects to its host organism.
Does gene duplication result in paralogs?
Paralogous genes (or paralogs) are a particular class of homologous genes. They are the result of gene duplication and the gene copies resulting from the duplication are called paralogous of each other.
How can gene duplication affect gene expression?
Most of the new-born duplicates lead to increased expression and are costly for the cell. So far, we have demonstrated that a duplicated gene offers a selective advantage provided the total gene expression level is maintained, with one or two copies (gene dosage sharing).
How does gene duplication increase genetic variation?
Gene and genome duplications provide a source of genetic material for mutation, drift, and selection to act upon, making new evolutionary opportunities possible. As a result, many have argued that genome duplication is a dominant factor in the evolution of complexity and diversity.
What disease does Duplication cause?
MECP2 duplication syndrome is a condition that occurs almost exclusively in males and is characterized by moderate to severe intellectual disability. Most people with this condition also have weak muscle tone in infancy, feeding difficulties, poor or absent speech, or muscle stiffness (rigidity).
What is the importance of gene duplication in evolution?
Gene duplication is an important mechanism for acquiring new genes and creating genetic novelty in organisms. Many new gene functions have evolved through gene duplication and it has contributed tremendously to the evolution of developmental programmes in various organisms.
Why Does gene duplication occur?
Gene duplication is the process by which a region of DNA coding for a gene is copied. Gene duplication can occur as the result of an error in recombination or through a retrotransposition event. Duplicate genes are often immune to the selective pressure under which genes normally exist.
What is the purpose of chromosome duplication?
Duplications typically arise from an event termed unequal crossing-over (recombination) that occurs between misaligned homologous chromosomes during meiosis (germ cell formation). The chance of this event happening is a function of the degree of sharing of repetitive elements between two chromosomes.
What disease is caused by translocation mutation?
Translocation Down syndrome is a type of Down syndrome that is caused when one chromosome breaks off and attaches to another chromosome. In this case, there are three 21 chromosomes but one of the 21 chromosomes is attached to another chromosome.
What does chromosome duplication cause?
During a disease process, extra copies of the gene can contribute to a cancer. Genes can also duplicate through evolution, where one copy can continue the original function and the other copy of the gene produces a new function. On occasion, whole chromosomes are duplicated. In humans this causes disease.