What is Genes: Definition and 112 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.

View More On Wikipedia.org
Recent contents Top users
  1. J

    The origins of recessive genes

    Hi everyone, I'm studying physics and not biological sciences, but I've been wondering about recessive genes recently. Given my background, do be kind on the explanations. My question is: if a recessive gene tends to be overcome by the dominant gene, how do recessive traits still display...
  2. A

    Recombinant dna technology-[how are specific genes chosen]?

    Recombinant dna technology-[how are specific genes chosen]?? IN recombinant dna technology,certain segments of dna are removed from one organism and put in another.How are are specific portions of DNA removed from certain animals and fused into others?? More importantly,how do scientists know...
  3. bohm2

    Are Genes Our Destiny? Scientists Uncover Hidden Code in DNA

    Flexible epigenetic code-are genes our destiny-? Are Genes Our Destiny? Scientists Discover 'Hidden' Code in DNA Evolves More Rapidly Than Genetic Code ScienceDaily (Sep. 16, 2011) — A "hidden" code linked to the DNA of plants allows them to develop and pass down new biological traits far...
  4. H

    Understanding how the genes actually work

    I have understood that one gene on the chromosome is coding for one special proteine (RNA), but a gene is also deciding which qualities we get. Is my human qualities based on genes or proteines? Is it the same thing, or is it two very different things? I asked the teacher and he said that our...
  5. n.karthick

    What are genes, chromosome and DNA?

    Hi I am not from biological background and I seek simple explanations for the above (genes, chromosome and DNA) I know plenty of material are available in net, but if some one explains me what they are and how they are connected in essence I would be grateful to him. These terms are repeatedly...
  6. Spinnor

    Cassava packs a protein punch with bean genes

    From this week's New Sceintist, "Cassava packs a protein punch with bean genes". http://www.newscientist.com/article/mg20927984.800-cassava-packs-a-protein-punch-with-bean-genes.html Free registration may be required to view the article. From the article, "A DEADLY poison could save the...
  7. A

    Scientists have tried to make the best fabric by using spiders genes

    I read on the net about how scientists have tried to make the best fabric by using spiders genes. They took a gene from the spider and inserted it into a goat's gene and then the milk which the goat gave, contained some silkiness, from which, after processing, scientists managed to extract...
  8. J

    Understanding Chromosomes and Genes: A Basic Overview for Non-Biology Students

    I'm not a biology student. So, I humbly request you to limit yourself to the basics, please do not indulge in infighting. If you ignore the request, you would be investing your efforts at the wrong place and perhaps it would be considered a pretentious show of knowledge. There are 23 pairs of...
  9. A

    Modified genes from crops in a GM crop trial have transferred

    Something I recently discovered So in some cases it appears that crosspollination between roundup ready gmo crops and some types of weeds has been happening. So other than sending out hordes of illegal immigrants with hoes to dug them all out, what possible solutions are there for this problem?
  10. R

    Genes are the reason for this and that

    There's constantly people saying that genes are the reason for this and that. But I don't get it, as far as I know we have somewhat of an understanding of what genes do. And if I'm not completely mistaken what genes do is encode a certain family of proteins and regulate their expression in the...
  11. sophiecentaur

    Medical Our genes, medical insurance and tax.

    Any insurance is, essentially, a gamble. Someone (a company) with more money than us is prepared to gamble, offering a huge stake (the payout) against our small stake (the premium). The Insurer works out the probability of a payout and calculates the premium that they want so that they make a...
  12. Kerrie

    My child with the recessive genes

    Biology is a science I know absolutely nothing about! My 4 year old has super light blond hair, fair skin and crystal blue eyes. Her father has dark brown hair, and greenish-brown eyes, and I have brown hair/eyes. How does this recessive gene work? My husband swears she wasn't switched...
  13. A

    Social Ideologies/Interests/Beliefs and Genes

    Hi, Are person's thoughts/interests/beliefs determined by genes and adjusted in the environment? Here is an examples: -A baby is born from a very religious family but was fostered/raised by a very atheistic family. Would the grown baby be inclined to think less rationally and believe...
  14. B

    Inheriting Genes from William the Conqueror to Elizabeth II

    This is not a homework question. It is actually kind of a biology question, but I'm dealing with the pure mathematics here. We came up with this reading "The selfish gene" by Richard Dawkins. He writes something like: "Elizabeth II is a direct decsendant William the conqueror. However it is...
  15. M

    DNA Transcription: Where do genes begin and end?

    Dear all, I'm studying DNA-Protein relationships for a computer simulation I have to make about it and I'm finding it difficult to understand how the RNA polymerase knows where to start and stop transcription on a strand of DNA. Could someone explain this for me? Let's assume that '['...
  16. C

    Frequency and Location of Genes

    Hello. I'm currently studying for Biology and I'm looking over the quizzes we took in class to see what I need work on. So far, I have trouble on frequency and location of genes. Here's one of the questions I missed on the quiz (my answers are in bold): A man with the recessive traits of...
  17. H

    What are Novel Genes? - Get Help Here

    Hi I don't know what novel genes are. Any help? Thanks
  18. L

    Do complementary genes move closer on the DNA chain?

    1. I read that each gene has a 50% chance to be transferred to a single gamete. Does the distance between two genes on the same chromosome influence the conditional probability for the second gene to be transferred to the same gamete as the first one? 2. Can the process of reproduction...
  19. B

    How are genes selected for combination in sperm and egg cells?

    I read that genes are selected at random from both chromosomes to be put together in the sperm or the egg. And that every sperm or egg has the potential of being a different human being. Exactly what is the process at which these genes are selected? thanks
  20. S

    Genes, memes and the third replicator

    This article would seem to fit in the computer science forum, but the types of questions there has me thinking this is a better forum to post this article. http://www.newscientist.com/article/mg20327191.500-evolutions-third-replicator-genes-memes-and-now-what.html?full=true
  21. T

    Biology Questions: Understanding Genes, Patents, and Chromosomes"

    A few Biology questions I was interested in finding an answer to... 1. How many genes are there? 2. How many are patented? 3. How many Y-chromosomes are there? 4. How many X-chromosomes are there?
  22. P

    Genes that Cause Human Aging: Telomeres, Klotho & Methuselah

    What genes cause aging, most people think shortening of telomeres is the main reason of aging, but I know there are more than that, like Klotho, Methuselah. But which fews are more important than others, and what else are there?
  23. T

    Pictures of people with these 'genes'?

    I am curious as to how people who are 1/2 white, 1/4 black and 1/4 Asian look like. A typical scenario is where one parent is white/asian and the other is white/black.
  24. B

    Orthologous vs Paralogous genes

    I am having trouble wrapping my mind around these concepts. Can anyone explain them clearly, and in relatively simple terms?
  25. B

    Can viruses be used to diminish the effects of genes?

    Can viruses be used to diminish the effects of genes? My friend said they couldn't be because we didn't understand enough about the mechanisms behind viruses and she gave some other reasons...but she was in a hurry and she might not have understood what i was asking...so I was wondering if a...
  26. T

    Linkage And Mapping Of Genes

    I would appreciate help with this problem, if at all possible! Homework Statement Snapdragons, homozygous for the recessive allele ls of the leaf form gene, have serrated leaves, the normal allele l+ is dominant and responsible for a smooth leaf phenotype. Individuals homozygous for the...
  27. R

    Exploring Genes: Commonalities and Differences in Animals and Plants

    Which gene is the commonest in the animal and plant world and why? Which gene makes a plant most different from an animal? If genes hadn't mutated in the past, how different would the world be today? If there was more to the genetic code than ATCG i.e five,six or seven building blocks for the...
  28. D

    Natural Selection: Selfish Genes & Egg's Reproductive Supremacy

    "A chicken is an egg's way of making another egg" IS reproductive superiority the basis of natural selection?
  29. D

    How do genes switch on and off in response to the environment?

    I wanted to know how genes switch on and off. I understand it is in response to the external environment of the organism and involves something called trancription factors, but I am not very sure of the mechanism. I have studied about operons but it seems to be a rather simplistic concept, not...
  30. Q_Goest

    What are some examples of genes being active in Slug cells?

    In a http://www.sciam.com/article.cfm?chanID=sa003&articleID=CF2AA0B2-E7F2-99DF-34CD01DE3E68F8ED&ref=rss", it says: What do they mean when they say 10,000 genes "could be active"? What are these genes doing in the brain cell which is interpreted as 'being active'?
  31. P

    Do genes really determine behaviour?

    From the blog "only a game": Is it true that an unknown (and currently unprovable) process is involved in the relation between genes and behaviour? Are there any ideas what this proces might be? And: Is it true that findings that link behaviour to genes are hardly ever replicated? If so...
  32. B

    Biology Help: Sperm & Egg Cells, Genes & Their Functions

    Biology Help ! Female cimpanzees often mate with more than one male. The different males' sperm cells race each other to reach the egg first. Both Modja and Tatu have mated with Tanu in the last hour. a) In which part of a sperm cell and an egg cell are the genes found? b) What do genes...
  33. S

    Genetic Link to Alcoholism and Obesity: A New Study in Molecular Psychiatry

    Are you a persistent drunk? Have you not seen your toes since you were a kid? You like to blame it on your genes, right? Now see this (new paper in the wonderfully titled journal Molecular Psychiatry - only the abstract is free, but that should suffice...
  34. K

    Genes themselves have memories, swtiches

    http://www.bbc.co.uk/sn/tvradio/programmes/horizon/ghostgenes.shtml Genes themselves have memories, swtiches, that could be turned on or off in one person `s lifetime, and passed on to that person `s offsprings. evidences are 1) grandparents that experienced famine, is correlated with...
  35. S

    Mom's diet can tinker with baby's genes

    http://www.nature.com/news/2006/060529/full/060529-10.html This reminds me of my mom saying that she changed her diet to be healther while she was pregenet.:uhh:
  36. D

    What is the current estimate for the number of genes in humans?

    Currently ? :) I was really disappointed with the internet when I tried to find this figure, all you can get are old articles, and with, in the best case, 30.000 genes estimate. This tells me that after great initial interest in this topic, interest has changed, in general public at least...
  37. Loren Booda

    Superfluous Genes: A Novel Theory on Genetic Adaptation and Survival

    May one add to Darwin's theory the possibility that we do not use most of our genes to adapt at every generation, but may pass down a large proportion of "superfluous genes," acting towards statistical survival for our progeny, even into the distant future, but not expressed in the environment...
  38. A

    Medical Maths and the Brain: Does It Run in Our Genes?

    erm..i always seem to relate maths to everything i think...i don't do it on purpose ..but when i think of people they always seem to have a corresponding maths symbol or even plain numbers...and they change throughout that thought. so one person doesn't all ways have an asociated(sp) maths...
  39. P

    New Research Reveals That Thoughts Affect Genes

    Is there any truth to this (are there actually scientific papers describing how thoughts affect genes) or is this a publicity stunt to promote his book? Liptons website
  40. N

    Genes to live a really extended lifetime

    Theoretically, could we (as a species) or could something else (as a species) evolve into something that lives a really really really really long time? I mean I really doubt that anything could actually become immortal because I think that the Universe will probably end at some point... But...
  41. N

    Medical Exploring the Possibility of Connecting Two Brains with Slime Mold Genes

    Do you think it would be possible to use slime mold genes to make one brain physically connect up to another brain? (To form one organ) Could you give info on that here? anyways if you want to give insight or anything please do so...it's 3:00 am though lol so I'm going to go to sleep soon
  42. T

    Screening for High-Risk Cancer Genes: Cost & Benefits

    My friend's family has a history of cancer, could she be screened for (genetic) markers that indicate high risk for certain cancers or something and how much would that cost and how helpful would it be thanks
  43. T

    Genes of a single-celled organism and the genes of a multi-cellular

    What is the difference between the genes of a single-celled organism and the genes of a multi-cellular organism? I mean could the genes of a single celled organism be used in a certain way in a multi-cellular organism? Thanks
  44. T

    Synthetic Genes: Exploring Man-Made Genes

    Hi I was talking to my friend and she said that it would be possible (maybe) to make synthetic genes and that those genes would be unique genes- she said they would be like plastic (because plastic doesn't occur in nature yet it's a combination of things that exist in nature) (Because the...
  45. R

    Genes that mice and humans share, 99% are identical

    I just read this We discovered during the sequencing of the genome that of the genes that mice and humans share, 99% are identical. BBC Four:*The sequencing of the mouse genome has had less publicity than the work on the human genome - do you think it is as significant in its way? CC:*Yes...
  46. G

    Using Poly-A Sequences & Isogenic/Null Cell Lines for Reporter Genes

    • Why should some Poly-A sequences lay upstream of a reporter gene? • Isogenic cell lines? • Null cell lines? Any ideas are greatly appreciated.
  47. N

    Interphase & Genes: Does Independent Assortment Occur?

    i know that during interphase dna gets replicated, gene expression gets regulated, but does independent assortment of genes occur in interphase? thanks
  48. M

    How do genes regulate cell abilities?

    What chemical reactions take place when genes "tell" cells what to do? I'll have more specific questions later but this will be a decent start.
  49. D

    Different types of available genes

    I have two important questions. First one is,Can somebody supply me any link or information about different types of available genes.for example during learning proces the genes that are responsible for this particular action.likewise all the actions that we do and the genes responsible for...
  50. S

    Active Genes & Protein Expression: Why Can't Active Genes Give LacZ Expression?

    all i learned about protein expression till now is gone, may i say, just because an explanation from my professor...i just hope that he was not right about this, since it turns my "world" up side down! the aim was to investigate the different expression degrees of the yeast genes. we used S...
Back
Top