What is Gene: Definition and 137 Discussions

In biology, a gene (from genos (Greek) meaning generation or birth or gender) is a basic unit of heredity and a sequence of nucleotides in DNA or RNA that encodes the synthesis of a gene product, either RNA or protein.During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gene–environment interactions. Some genetic traits are instantly visible, such as eye color or the number of limbs, and some are not, such as blood type, the risk for specific diseases, or the thousands of basic biochemical processes that constitute life.
Genes can acquire mutations in their sequence, leading to different variants, known as alleles, in the population. These alleles encode slightly different versions of a protein, which cause different phenotypical traits. Usage of the term "having a gene" (e.g., "good genes," "hair color gene") typically refers to containing a different allele of the same, shared gene. Genes evolve due to natural selection / survival of the fittest and genetic drift of the alleles.
The concept of gene continues to be refined as new phenomena are discovered. For example, regulatory regions of a gene can be far removed from its coding regions, and coding regions can be split into several exons. Some viruses store their genome in RNA instead of DNA and some gene products are functional non-coding RNAs. Therefore, a broad, modern working definition of a gene is any discrete locus of heritable, genomic sequence which affect an organism's traits by being expressed as a functional product or by regulation of gene expression.The term gene was introduced by Danish botanist, plant physiologist and geneticist Wilhelm Johannsen in 1909. It is inspired by the ancient Greek: γόνος, gonos, that means offspring and procreation.

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  1. I

    Transcription Factor Inhibition vs. Gene Methylation?

    I may mess up this question, and this is not my strong field of knowledge. I am wanting to understand different ways of genes not expressing themselves. So far I have come across two ways this happens (perhaps there are more?) - "transcription factors that inhibit gene transcription" - "genes...
  2. PainterGuy

    Medical Curly hair gene, straight hair gene

    Hi, One of my cousins had a baby almost six months ago. The baby's father has straight hair and mother has very curly hair. After almost six months, the baby's hair started looking somewhat wavy. By "wavy" I mean a little curly. Out of curiosity, I wanted to see which gene is dominant - curly...
  3. S

    Questions Regarding Methods of Gene Cloning

    I have been told that the traditional restriction digestion cloning method, where you use restriction enzyme to produce sticky ends in the gene of interest and the plasmid vector, is vulnerable to contamination. The lecturer proceeds to conclude that Gibson Assembly Cloning is therefore a...
  4. S

    Biology Which method would be wrong to use for gene expression?

    I've been struggling, no matter what I try to do I can't come up with a solution. The answer is in situ, but in my mind it would work perfectly fine. The only thing we would do is just use an RNA probe complementary to the gene we are trying to detect and it should light up the moment the gene...
  5. F

    Is gene replacement a practical way to fix random mutations?

    Recently I asked if prime editing can be used to reverse the random mutations we accumulate with aging(https://www.physicsforums.com/threads/can-prime-editing-fix-every-harmful-mutation-in-all-our-cells.1003279/) but now I have a different question. Can we simply replace our genes to get rid of...
  6. F

    Can current gene editing technologies reverse age related mutations?

    How can current gene editing technologies like Prime Editing can be used to reverse all age related mutations that negatively affect some type of cell like neurons?. According to this article (you need to click on the "toggle reader view" button in firefox in order to read it without registering...
  7. Rongeet Banerjee

    Are Multiple Allelism and Gene Polymorphism the same?

    Is Multiple Allelism and Gene Polymorphism same ?If not then why?
  8. PainterGuy

    How does gene regulation result in differentiation of different organs?

    I don't know much about biology but the following two questions have always puzzled me. 1: If each human body cell contains the same genes (from 20,000 to 25,000) then how different cells in different parts of body do different things. A liver cell, for example, does not have the same...
  9. Ygggdrasil

    Medical Progress for Gene Therapy and CRISPR against Blood Diseases

    The New England Journal of Medicine published two papers showing data for successful treatment of a handful of patients with sickle cell disease or β- thalassemia using gene therapy techniques. Both teams used the strategy of inhibiting the BCL11a transcription factor in blood cells, which...
  10. mark!

    Giant viruses: gene capture or redundancy?

    Is it more probable that giruses (giant viruses) acquired their cellular apparatus from another cell, or that they once were a functioning cell, but degraded over time, parasitizing other cells? In the course of evolution viruses emerged many times. Viruses evolved on multiple, independent...
  11. TytoAlba95

    How have scientists derived the gene sequences known today?

    I know that human genome sequencing was done by 2001. Inintially there were Maxam-Gilberth technique, then Sanger's technique and then finally NGS techniques have made sequening faster and efficient. My question is, though we are able to sequence the whole genome, how have scientists arrived at...
  12. jaumzaum

    How many alleles per gene the human species have today?

    Hello. Yesterday I was making some calculations, and I started to wonder the average number of alleles per gene the human specie have today. The best question would be how many mutations per base or how many alleles in an average 1000 base gene, as genes vary in size. What made me wonder this...
  13. C

    Compute steady states of gene expression

    Homework Statement A bacteria that normally divides every 20 minutes express gene X. The production rate of protein X is 5nM/min. The protein is stable and does not degrade. What is the concentration of X in the steady state?The same bacteria enter into a stress state at t=0 for 3 hours...
  14. Ygggdrasil

    Measuring off target mutations during CRISPR gene editing

    https://www.physicsforums.com/insights/dont-fear-https://www.physicsforums.com/insights/dont-fear-crispr-new-gene-editing-technologies-wont-lead-designer-babies/-new-gene-editing-technologies-wont-lead-designer-babies/ is a newly developed tool that allows researchers to easily make changes to...
  15. DaveC426913

    Software bugs and gene mutations

    Couldn't figure out which category to put this in so I put it here. Today, the Product Owner stumbled across a feature that was working correctly, but should not have been. A Yes/No button was defaulting to 'Yes'. It was eventually supposed to be implemented that way, but no one was assigned...
  16. I

    Does histone H3K9 de-acetylation stop gene expression?

    I've read in a few places that acetylation of histones creates transcription activation rather than repression (the common example being: H3K9). What I am curious, with the absence of this acetylation (I'm guessing this would the process de-acetylation), do the genes that were previously...
  17. Xena Dean

    Determination of a dominant and a recessive trait or gene

    What determines if a gene or trait will be dominant over another or not? For instance, we take the example of widow's peak. This gene has two alleles. One for widow's peak which is the dominant one, and another for straight line, which is the recessive one. But why the widow's peak is dominant...
  18. Rayanna

    Introduction of antibiotic resistance gene to a bacteria

    Why would anyone like to intoduce a antibiotic gene in a bacteria if it will make it resistant to antibiotics which is not of any advantages to humans?
  19. Wrichik Basu

    Gene for allergies and the common cold

    Some people are more susceptible to allergies and common cold than others. For example, my mother and I suffer from dust allergies and blocked nostrils throughout the year. In fact, last year or so, my mother had to be hospitalised as her lungs had become stiff due to sudden allergy. Almost...
  20. JonMoulton

    Which gene expressions start to happen in an embryo

    Watching dynamics of RNA expression - paper describing a visualization technique. Movie 1 from supplemental information: in a zebrafish embryo, DNA is stained with red fluorescence and carboxyfluoresceinaed Morpholino oligos targeting dre-miR-430 emit visible green fluorescence when they reach...
  21. Ygggdrasil

    Celebrating RNA Day: Exploring the Diverse Roles of RNAs in Gene Expression

    Today (AUG 1) is RNA Day, an international celebration of one of the most versatile biomolecules in existence. What are some areas of RNA research that excite you most? Some of the most intriguing areas of current research to me (with example links for further reading): The role of RNAs in...
  22. V

    Where does the gene for green color come from?

    I was studying evolution and speciation and an example was given in my textbook. It said that there is a species of red beetles and through variation a green beetle is formed and then is naturally selected as red beetles are easily seen by crows and green are not. My question is where does the...
  23. MrGenetic

    Gene Manipulation / Transformation

    Hi. If we want cell to accept vector dna in transformation, we treated with calcium chloride or chilled on ice etc.. But i have a trouble with one issue about that. Books say that ; We must choose the vector that specific according to the cell that will do transformation. But we will treat with...
  24. klotza

    Insights Using the Spaghetti-Twist to Align DNA - Comments

    Greg Bernhardt submitted a new PF Insights post Using the Spaghetti-Twist to Align DNA Continue reading the Original PF Insights Post.
  25. BillTre

    New Brain Gene Therapies Dramatic Success

    This Science magazine news article describes several recent successes and the technical advances that helped them along. One important advance was finding better viruses that could pass the blood brain barrier and infect more specific sets of cells by screening through a bunch of samples from...
  26. A

    Probabilities of the gene appearing that made humans smart?

    What exactly was the probability of the genes manifesting that give rise to human intelligence? The event must be incredibly rare seeing how there were several species of animals yet humans are the only one who can do complex math and language.
  27. I

    Do genes "fight" to get expressed?

    I am not sure if this is an epigenetic question or not, I am not too familiar with this field, so I hope it makes sense. Do genes ever “fight” to express themselves? I guess they do initially when time comes for it to be decided which one gets expressed? Is one gene "stronger"? Is there an...
  28. T

    What is linkage strength between gene loci?

    Homework Statement In linkage strength between any two gene loci is 70%,what would be the amount of crossing over between these loci? (a) 15% (b)30% (c) 70% (d) none of these. 2. My approach at understanding the concept I didn't find much about linkage strength from any authentic source. I...
  29. caters

    X linked gene but more common in females?

    I am writing a genetics guide for my fictional cats. I know that most of it isn't actual cat genetics but it is still genetics. There is 1 particular set of pattern genes that is more commonly expressed in females than in males, the lion pattern. I haven't decided yet whether it should be...
  30. rfranceschetti

    Medical Gene flow in hypothetical genetically engineered humans

    Hi all, It has come to my attention this article on PF (https://www.physicsforums.com/insights/can-gene-editing-eliminate-alzheimers-disease/) about a genetic approach to prevent Alzheimer's disease, based on applying gene-editing techniques on human embryos. In short (so not to be...
  31. Ygggdrasil

    Medical Gene Therapy Successfully Treats Teenage Boy with Sickle Cell Anemia

    *in one patient, for at least 15 months Research published this week in the New England Journal of Medicine reports on a case of using gene therapy to potentially cure a teenage boy of sickle cell anemia, a genetic disease that impairs red blood cell function...
  32. Ygggdrasil

    Medical National Academies Recommendations on Human Gene Editing

    This week on, Feb 14, the US National Academy of Sciences and National Academy of Medicine released a report giving recommendations on how...
  33. Astronuc

    RIP Gene Cernan, last astronaut on the moon

    HOUSTON (AP) -- Former astronaut Gene Cernan, who as the last person to walk on the moon returned to Earth with a message of "peace and hope for all mankind," died on Monday, his family said. He was 82. https://www.yahoo.com/news/gene-cernan-last-astronaut-moon-205711702.html On Dec. 11, 1972...
  34. I

    What is the term for a gene and its corresponding protein?

    Hello again! Is there a common word/term for a gene and the protein that it codes for? I know there is signal transduction, but that would be for a whole set of genes and proteins doing a stream of functions. But would there be a name for the specific gene/protein "bundle"?
  35. physicist007

    Y Gene Domination: Male Progeny or Female Progeny?

    When the genotype of zygote is heterozygous XY then it results into a male progeny while to obtain a female progeny homozygous XX conditions are needed. Although homozygous YY condition is not possible in nature, but can we say that Y gene seems dominant??
  36. W

    Is The Selfish Gene Still Relevant in Evolutionary Science Today?

    I'm thinking of getting this book as one of my proper introductory reads to evolution but I have one burning question: How does Prof Dawkins' book stand in terms of evidence? Are most of the ideas put forth in the book still standing strong today and most importantly, is it a worthwhile read...
  37. BillTre

    Structural Choromsomal Hierarchies and Gene Expression

    There have been occasionally questions/comments about gene control. This should feed the hunger for knowledge. Here is an open access review article: Three-Dimensional Genome Organization and Function in Drosophila. It discusses some not widely known aspects of control of gene expression in...
  38. 1oldman2

    Medical China begins gene editing trial

    I came across this article, thought it was worth mentioning. http://www.nature.com/news/crispr-gene-editing-tested-in-a-person-for-the-first-time-1.20988 A Chinese group has become the first to inject a person with cells that contain genes edited using the revolutionary CRISPR-Cas9 technique...
  39. DennisN

    Who Was the Hilarious Actor Behind These Unforgettable Characters?

    Gene Wilder (1933 – 2016) He was one of my favorite comic actors because of his timing, performances and the number of quite unusual and hilarious characters he played. He gave me many, many good laughs in movies, particularly Start The Revolution Without Me, The Adventure of Sherlock Holmes'...
  40. Ygggdrasil

    What Are Effective Methods to Investigate Gene Downregulation in Cancer?

    I am studying a particular gene whose expression decreases in certain types of cancer. I'm interested in finding out the mechanisms for this downregulation, specifically, which transcription factors and signalling pathways are involved. I have a hypothesis for the pathway involved, but in case...
  41. Clever Penguin

    Writing: Input Wanted The Immortal Gene: Uncovering Biological Immortality

    I have started writing a book based on the writing prompt: 'Not a single person in the world has died for over a year. Write a story about it.' I decided to call mine 'The Immortal Gene.' The only difference between this universe and 'TIG Universe' is that in 'TIG Universe' everyone who is...
  42. Docscientist

    Genetic Confusion: The Eye Color Dilemma Explained

    Say a girl has brown eyes .she meets with an accident which causes her to undergo an eye transplantation.The donor has blue eyes and the girl gets them.Now does she possesses a blue or brown eye ? So she genetically has brown eyes but phenotypically has blue eyes ? Is it like that? But phenotype...
  43. I

    Genes and protein they code size relation?

    If the gene is smaller, is the protein that it codes for smaller too? Vice versa?
  44. I

    Can gene structure determine its "strength"?

    Are certain DNA (genetic) strands structurally better build for survival than others? If yes, is there a term for this? For example, is there a specific order of nucleotides that is harder to destroy than another? Or if there is a specific order/combination of nucleotides that would have...
  45. R

    Gene Cloning Problem: Insulin Gene Multiplication Mistake

    Homework Statement Molecular cloning experiments are carried out to generate multiple copies of a gene of interest. In one such experiment carried out at a student lab, the gene coding for insulin is multiplied in a bacterial cell. In the screening step, the students realized that they have...
  46. Ygggdrasil

    Exploring the Ring of Life: Horizontal and Vertical Gene Transfer

    Since the time of Darwin, biologists have looked at the history of life as a tree showing how the common ancestor of all life gave rise to all extant species. However, as we have learned more about biology, we've found that organisms do not inherit genetic information from only their direct...
  47. 24forChromium

    To what extent does meme substitute gene

    A specie of organisms can inherit traits to its next generation through gene. For example, leaf-cutter ants' ancestors passed their instinct of leaf-cutting to its offspring via gene. In the case of organisms capable of learning, such as crows, certain traits can be passed through generations...
  48. A

    Question about biology - gene mapping

    Homework Statement Homework Equations RF = (#Recombinants)/(Total offspring) x 100 The Attempt at a Solution How do I know that b is unlinked? I know that unlinked genes have a recombination frequency of 50% or higher, but how do I calculate RF for the genes here?
  49. Eagle9

    How many levels of gene control exists?

    We know that some genes produce mRNAs (and then proteins) and some other genes produces just ncRNAs (non-coding RNA) that play regulatory roles (yes, I know that some ncRNAs play other roles, but let’s forget about them now). I want to know a bit more about this regulatory processes. Does every...
  50. Ygggdrasil

    Insights Can Gene Editing Eliminate Alzheimer's Disease? - Comments

    Ygggdrasil submitted a new PF Insights post Can Gene Editing Eliminate Alzheimer's Disease? Continue reading the Original PF Insights Post.