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Please research the article's assertions. Whatever is credible should be sourced, and what is not should be removed. </p> </td></tr></tbody></table> <table class="messagebox mb-brainwatermark plainlinks mb-info" style=""> <tbody><tr> <td class="mb-image"><a href="/wiki/File:Information_icon.svg" class="image"><img alt="Information icon.svg" src="/w/images/thumb/3/35/Information_icon.svg/50px-Information_icon.svg.png" decoding="async" width="50" height="50" srcset="/w/images/thumb/3/35/Information_icon.svg/75px-Information_icon.svg.png 1.5x, /w/images/thumb/3/35/Information_icon.svg/100px-Information_icon.svg.png 2x" data-file-width="620" data-file-height="620" /></a> </td> <td class="mb-text"><b>This article requires expansion.</b> Please <b><a rel="nofollow" class="external text" href="https://rationalwiki.org/w/index.php?title=Genetics&action=edit">help</a>.</b> <p>Though not a <b><a href="/wiki/RationalWiki:Stub" title="RationalWiki:Stub">stub</a></b> by pure word count, this article lacks depth of content. </p> </td></tr></tbody></table> <table class="infobox" cellpadding="1" cellspacing="0" style="float: right; margin: 0 0 0.5em 0.5em; text-align:left; border: 1px solid #5959DA; width:175px;"> <tbody><tr> <td style="font-size: 95%; text-align:center; color:White; background-color:#5959DA"><b>We're all Homo here</b><br /><a href="/wiki/Evolution" title="Evolution"><font size="5" color="White"><b>Evolution</b></font></a> </td></tr> <tr> <td style="background-color:#E0E0F0;" align="center"><a href="/wiki/Category:Evolution" title="Category:Evolution"><img alt="Icon evolution.svg" src="/w/images/thumb/5/5c/Icon_evolution.svg/100px-Icon_evolution.svg.png" decoding="async" width="100" height="100" srcset="/w/images/thumb/5/5c/Icon_evolution.svg/150px-Icon_evolution.svg.png 1.5x, /w/images/thumb/5/5c/Icon_evolution.svg/200px-Icon_evolution.svg.png 2x" data-file-width="200" data-file-height="200" /></a> </td></tr> <tr> <td style="font-size: 95%; color:White; background-color:#5959DA; text-align:center;"><b>Relevant Hominids</b> </td></tr> <tr> <td style="font-size: 95%; background-color:#E0E0F0;"> <ul><li><a href="/wiki/Charles_Darwin" title="Charles Darwin">Charles Darwin</a></li> <li><a href="/wiki/Alfred_Russel_Wallace" title="Alfred Russel Wallace">Alfred Russel Wallace</a></li> <li><a href="/wiki/Gregor_Mendel" title="Gregor Mendel">Gregor Mendel</a></li> <li><a href="/wiki/Richard_Dawkins" title="Richard Dawkins">Richard Dawkins</a></li> <li><a href="/wiki/Jerry_Coyne" title="Jerry Coyne">Jerry Coyne</a></li></ul> </td></tr> <tr> <td style="font-size: 95%; color:White; background-color:#5959DA; text-align:center;"><b>A Gradual Science</b> </td></tr> <tr> <td style="font-size: 95%; background-color:#E0E0F0;"> <ul><li><a href="/wiki/Origins_debate" title="Origins debate">Origins debate</a></li> <li><a href="/wiki/Fitness" title="Fitness">Fitness</a></li> <li><a href="/wiki/Hopeful_monster" title="Hopeful monster">Hopeful monster</a></li> <li><a href="/wiki/Mae-Wan_Ho" title="Mae-Wan Ho">Mae-Wan Ho</a></li></ul> </td></tr> <tr> <td style="font-size: 95%; color:White; background-color:#5959DA; text-align:center;"><b>Plain Monkey Business</b> </td></tr> <tr> <td style="font-size: 95%; background-color:#E0E0F0;"> <ul><li><a href="/wiki/Young_Earth_Creationism" class="mw-redirect" title="Young Earth Creationism">Young Earth Creationism</a></li> <li><a href="/wiki/Old_Earth_Creationism" class="mw-redirect" title="Old Earth Creationism">Old Earth Creationism</a></li> <li><a href="/wiki/Intelligent_Design" class="mw-redirect" title="Intelligent Design">Intelligent Design</a></li> <li><a href="/wiki/Microevolution" class="mw-redirect" title="Microevolution">Microevolution</a> vs. <a href="/wiki/Macroevolution" class="mw-redirect" title="Macroevolution">Macroevolution</a></li></ul> <div class="vte plainlinks" style="font-size:smaller; text-align:center;"><a href="/wiki/Template:Evolution" title="Template:Evolution">v</a> - <a href="/wiki/Template_talk:Evolution" title="Template talk:Evolution">t</a> - <a rel="nofollow" class="external text" href="https://rationalwiki.org/w/index.php?title=Template:Evolution&action=edit">e</a></div> </td></tr></tbody></table><div role="note" class="hatnote">Not to be confused with <a href="/wiki/Genetic_fallacy" title="Genetic fallacy">genetic fallacy</a>.</div> <p><b>Genetics</b> refers to the study of heredity, <a href="/wiki/Gene" class="mw-redirect" title="Gene">genes</a> and genetic material.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1">[1]</a></sup> Modern genetics examines how individual genes function and are expressed within the broader context of genomics, which focuses on analyzing the entirety of an organism's genetic material, and how these genetic elements interact with environmental factors to influence traits and disease.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2">[2]</a></sup> </p> <div id="toc" class="toc" role="navigation" aria-labelledby="mw-toc-heading"><input type="checkbox" role="button" id="toctogglecheckbox" class="toctogglecheckbox" style="display:none" /><div class="toctitle" lang="en" dir="ltr"><h2 id="mw-toc-heading">Contents</h2><span class="toctogglespan"><label class="toctogglelabel" for="toctogglecheckbox"></label></span></div> <ul> <li class="toclevel-1 tocsection-1"><a href="#Mendel_and_his_peas"><span class="tocnumber">1</span> <span class="toctext">Mendel and his peas</span></a></li> <li class="toclevel-1 tocsection-2"><a href="#Non-sexual_gene_transmission"><span class="tocnumber">2</span> <span class="toctext">Non-sexual gene transmission</span></a></li> <li class="toclevel-1 tocsection-3"><a href="#Modern_fields_of_study"><span class="tocnumber">3</span> <span class="toctext">Modern fields of study</span></a> <ul> <li class="toclevel-2 tocsection-4"><a href="#Sequencing"><span class="tocnumber">3.1</span> <span class="toctext">Sequencing</span></a></li> <li class="toclevel-2 tocsection-5"><a href="#Gene_expression"><span class="tocnumber">3.2</span> <span class="toctext">Gene expression</span></a> <ul> <li class="toclevel-3 tocsection-6"><a href="#Personality_effects"><span class="tocnumber">3.2.1</span> <span class="toctext">Personality effects</span></a></li> </ul> </li> </ul> </li> <li class="toclevel-1 tocsection-7"><a href="#Polymerase_chain_reaction_.28PCR.29"><span class="tocnumber">4</span> <span class="toctext">Polymerase chain reaction (PCR)</span></a></li> <li class="toclevel-1 tocsection-8"><a href="#Genetics_before_science"><span class="tocnumber">5</span> <span class="toctext">Genetics before science</span></a></li> <li class="toclevel-1 tocsection-9"><a href="#Evolution"><span class="tocnumber">6</span> <span class="toctext">Evolution</span></a></li> <li class="toclevel-1 tocsection-10"><a href="#See_also"><span class="tocnumber">7</span> <span class="toctext">See also</span></a></li> <li class="toclevel-1 tocsection-11"><a href="#External_links"><span class="tocnumber">8</span> <span class="toctext">External links</span></a></li> <li class="toclevel-1 tocsection-12"><a href="#References"><span class="tocnumber">9</span> <span class="toctext">References</span></a></li> </ul> </div> <h2><span class="mw-headline" id="Mendel_and_his_peas">Mendel and his peas</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=1" title="Edit section: Mendel and his peas">edit</a><span class="mw-editsection-bracket">]</span></span></h2> <p><a href="/wiki/Gregor_Mendel" title="Gregor Mendel">Mendel</a>'s famous experiments with peas pointed the way to the information that results in visible traits being binary in nature. It has since been established that the <a href="/wiki/DNA" title="DNA">DNA</a> <a href="/wiki/Molecule" title="Molecule">molecules</a> in the nucleus of <a href="/wiki/Cell" title="Cell">cells</a> carry this information, on pairs of <a href="/wiki/Chromosome" title="Chromosome">chromosomes</a>. Of these pairs of chromosomes, in each living creature, one originates from each parent (in the case of <a href="/wiki/Sex" title="Sex">sexually</a> reproducing <a href="/wiki/Species" title="Species">species</a>). This results in a continual mixing of traits present in a species across individuals. </p> <h2><span class="mw-headline" id="Non-sexual_gene_transmission">Non-sexual gene transmission</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=2" title="Edit section: Non-sexual gene transmission">edit</a><span class="mw-editsection-bracket">]</span></span></h2> <p>Non-sexually reproducing organisms pass on genetic information to their offspring which is identical to their own, whether through division of single celled organisms like <a href="/wiki/Bacteria" title="Bacteria">bacteria</a>, or various forms of <a href="/wiki/Cloning" title="Cloning">cloning</a> used by many <a href="/wiki/Plant" title="Plant">plants</a> (budding, spreading via root systems, or layering of above-ground stalks that grow new roots and become independent). Many organisms, especially plants, are capable of sexual and asexual reproduction, with some alternating between the two from generation to generation. </p> <h2><span class="mw-headline" id="Modern_fields_of_study">Modern fields of study</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=3" title="Edit section: Modern fields of study">edit</a><span class="mw-editsection-bracket">]</span></span></h2> <p>Genetics has moved far beyond the simple tracking of traits from parent to child, however, from the identification of the <a href="/wiki/DNA" title="DNA">DNA</a> <a href="/wiki/Molecule" title="Molecule">molecule</a> by Watson, <a href="/wiki/Francis_Crick" title="Francis Crick">Crick</a>, and Russell, through the modern sequencing of the <a href="/wiki/Human" title="Human">human</a> <a href="/wiki/Genome" title="Genome">genome</a> and the addition or subtraction of traits from existing species by <a href="/wiki/Genetic_modification" title="Genetic modification">genetic engineering</a>. </p> <h3><span class="mw-headline" id="Sequencing">Sequencing</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=4" title="Edit section: Sequencing">edit</a><span class="mw-editsection-bracket">]</span></span></h3> <p>Sequencing is the identification of the exact genetic code in the genome, in order to identify variant alleles, deletions, and insertions. </p><p><i>Next-Generation</i> 'high-throughput' sequencing machines can process large amounts of material, and are used for <i>Whole Gnome Sequencing</i> (WGS), whole exome sequencing (looking at the subset of the entire genome that 'codes' for genes) or other subsets of the genome that the scientists can tailor the 'kit' to match. A common approach uses 'shotgun sequencing', where the strands of DNA are broken up into chunks that are read by the machine in no particular order. Substantial computational effort is then needed to work out where each chunk belongs. </p><p><i>Sanger Sequencing</i> is an older method, less suited to sequencing such large regions, but is considered the 'gold standard'. It is often used where the region of interest is small, such as when validating results obtained from next-Gen sequencing. </p><p>In all traditional sequencing methods, the genetic material is a blend of that from a number of cells. Ideally, these cells will be of the same kind and thus be interchangeable. This is not always the case in practice and can play hob with the analysis. In particular, tumour cells can be very different to their neighbors, and those differences can have important consequences for treatment or diagnosis. A very recent development is that of <i>single-cell sequencing</i>, whereby single cells are isolated and sequenced separately. When it works, it provides higher quality analysis, better characterisation of tumours and reduces the need to 'purify' a sample down to a single cell type before sequencing, in cases where multiple cell types are of interest. When it works. </p> <h3><span class="mw-headline" id="Gene_expression">Gene expression</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=5" title="Edit section: Gene expression">edit</a><span class="mw-editsection-bracket">]</span></span></h3> <p>Expression analysis takes a different approach, measuring the <i>number</i> of chunks associated with each particular gene rather than any variants within them. This measures differences in gene regulation between samples. This is generally done to test the difference in regards to two or more different environmental factors. This is your brain on drugs, indeed. </p> <h4><span class="mw-headline" id="Personality_effects">Personality effects</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=6" title="Edit section: Personality effects">edit</a><span class="mw-editsection-bracket">]</span></span></h4> <p>One area of study is how genes can influence people's personality, this is often a study of things like the heritability of temperament traits.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3">[3]</a></sup> This combines psychology with molecular genetics, and neuroscience, so it is a multi-disciplinary approach to understanding how much genes contribute to personality.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4">[4]</a></sup> Nature or nurture is likely missing the point, which is that both nature and nurture play a role in shaping a person's personality. This is necessary because genes interact with the environment given context through a process best described by a complimentary field to genetics, which is epigenetics. </p> <h2><span id="Polymerase_chain_reaction_(PCR)"></span><span class="mw-headline" id="Polymerase_chain_reaction_.28PCR.29">Polymerase chain reaction (PCR)</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=7" title="Edit section: Polymerase chain reaction (PCR)">edit</a><span class="mw-editsection-bracket">]</span></span></h2> <div class="thumb tright"><div class="thumbinner" style="width:102px;"><a href="/wiki/File:DNArot.gif" class="image"><img alt="" src="/w/images/6/62/DNArot.gif" decoding="async" width="100" height="200" class="thumbimage" data-file-width="100" data-file-height="200" /></a> <div class="thumbcaption"><div class="magnify"><a href="/wiki/File:DNArot.gif" class="internal" title="Enlarge"></a></div>Brought to you by <a href="/wiki/LSD" title="LSD">LSD</a>.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5">[5]</a></sup> Or maybe scientists just have ways to cope with their workload.</div></div></div> <p>PCR is the straightforward process of amplifying a small amount of DNA in vitro, producing many copies. It is a simple extension of the DNA replication process. It involves a pair of primers (usually 20-30 bps in length) flanking the DNA target sequence. This allows a DNA polymerase enzyme to start the process of adding nucleotides (DNA polymerase needs a free 3' end to add nucleotides). The DNA polymerase used is usually Taq polymerase (isolated from the bacterium <i>Thermus aquaticus</i>, found in the hot springs in <a href="/wiki/Yellowstone" title="Yellowstone">Yellowstone</a> National Park) as it is heat stable (although there are other heat stable DNA polymerase enzymes available, e.g. Pfu polymerase). The enzyme and primers are added into the reaction vessel, along with deoxynucleotide triphosphates and the template DNA (total reaction volume is usually about 50-100μL). This vessel is placed in a PCR machine, which runs for 30 cycles usually, with each cycle consisting of a denaturation at 94°C (DNA is denatured to allow primers access), annealing at 60°C (primers and free nucleotides hydrogen bond to complementary DNA) and an extension step at 72°C (DNA polymerase starts at the primer then moves along bonding free nucleotides together and forming a complimentary strand of DNA). This technique has had an immense impact on molecular biology, forensic science and the diagnosis of human genetic diseases. </p> <h2><span class="mw-headline" id="Genetics_before_science">Genetics before <a href="/wiki/Science" title="Science">science</a></span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=8" title="Edit section: Genetics before science">edit</a><span class="mw-editsection-bracket">]</span></span></h2> <p>For thousands of years before the mechanisms were understood, man has been genetically engineering, by <a href="/wiki/Artificial_selection" title="Artificial selection">selective breeding</a>, food crops and domesticated animals to improve their flavor, yield, hardiness, and behavior. </p> <h2><span class="mw-headline" id="Evolution">Evolution</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=9" title="Edit section: Evolution">edit</a><span class="mw-editsection-bracket">]</span></span></h2> <p>The genes that underlie the passing on of traits are one of the fundamental building blocks of the process of <a href="/wiki/Evolution" title="Evolution">evolution</a>. </p> <h2><span class="mw-headline" id="See_also">See also</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=10" title="Edit section: See also">edit</a><span class="mw-editsection-bracket">]</span></span></h2> <ul><li><a href="/wiki/Gene" class="mw-redirect" title="Gene">Gene</a></li> <li><a href="/wiki/Evolution" title="Evolution">Evolution</a></li> <li><a href="/wiki/Inbreeding" title="Inbreeding">Inbreeding</a></li> <li><a href="/wiki/CRISPR" title="CRISPR">CRISPR</a></li></ul> <h2><span class="mw-headline" id="External_links">External links</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=11" title="Edit section: External links">edit</a><span class="mw-editsection-bracket">]</span></span></h2> <ul><li><a rel="nofollow" class="external text" href="http://www.genetics.org/">genetics.org</a></li></ul> <h2><span class="mw-headline" id="References">References</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Genetics&action=edit&section=12" title="Edit section: References">edit</a><span class="mw-editsection-bracket">]</span></span></h2> <div class="references-small" style="font-size:90%;"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><a href="#cite_ref-1">↑</a></span> <span class="reference-text"><a rel="nofollow" class="external autonumber" href="https://www.britannica.com/science/genetics">[1]</a>, Encyclopedia Britannica. (2024, December 3). Genetics. <a rel="nofollow" class="external free" href="https://www.britannica.com/science/genetics">https://www.britannica.com/science/genetics</a></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><a href="#cite_ref-2">↑</a></span> <span class="reference-text"><a rel="nofollow" class="external autonumber" href="https://www.nature.com/articles/s41576-020-0272-6">[2]</a>, McGuire, A. L., et al. "The road ahead in genetics and genomics." Nature Reviews Genetics 21.10 (2020): 581-596.</span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><a href="#cite_ref-3">↑</a></span> <span class="reference-text"><a rel="nofollow" class="external autonumber" href="https://medlineplus.gov/genetics/understanding/traits/temperament/">[3]</a> Medline.</span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><a href="#cite_ref-4">↑</a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://opentextbc.ca/introductiontopsychology/chapter/11-3-is-personality-more-nature-or-more-nurture-behavioral-and-molecular-genetics/">Is Personality More Nature or More Nurture? Behavioural and Molecular Genetics</a> Introduction to Psychology – 1st Canadian Edition.</span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><a href="#cite_ref-5">↑</a></span> <span class="reference-text">David Nutt (February 28, 2021). <a rel="nofollow" class="external text" href="https://www.sciencefocus.com/the-human-body/how-psychedelics-lsd-work-brain/">"Your brain on LSD: a guide through the most mind-blowing psychedelics research"</a>. <i>BBC Science Focus</i>. Quote: "<a href="/wiki/Francis_Crick" title="Francis Crick">Francis Crick</a>, who discovered the double helix structure of DNA with James Watson, and <a href="/wiki/Kary_Mullis" title="Kary Mullis">Kary Mullis</a>, who invented the polymerase chain reaction (PCR), had both taken the drug, and attributed some of their understanding and insights to it. Mullis has gone so far as to say: 'would I have invented PCR if I hadn’t taken LSD? I seriously doubt it… [having taken LSD] I could sit on a DNA molecule and watch the polymers go by. I learnt that partly on psychedelic drugs.'"</span> </li> </ol></div></div>    </div></div><div class="printfooter">Retrieved from "<a dir="ltr" href="https://rationalwiki.org/w/index.php?title=Genetics&oldid=2698851">https://rationalwiki.org/w/index.php?title=Genetics&oldid=2698851</a>"</div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Special:Categories" title="Special:Categories">Categories</a>: <ul><li><a href="/wiki/Category:Evolution" title="Category:Evolution">Evolution</a></li><li><a href="/wiki/Category:Biology" title="Category:Biology">Biology</a></li><li><a href="/wiki/Category:Genetics" title="Category:Genetics">Genetics</a></li><li><a href="/wiki/Category:Science" title="Category:Science">Science</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Pages_using_DynamicPageList_parser_function" 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