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Personal genomics

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<p><strong>Personal genomics</strong> is a branch of genomics where individual genomes are genotyped and analyzed using bioinformatics tools. It is also related to traditional population genetics. The genotyping stage can have many different experimental approaches including <a class="mw-redirect" title="Single nucleotide polymorphism" href="http://en.wikipedia.org/wiki/Single_nucleotide_polymorphism">single nucleotide polymorphism</a> (SNP) chips (typically 0.02% of the genome), or partial or full <a title="DNA sequencing" href="http://en.wikipedia.org/wiki/DNA_sequencing">genome sequencing</a>. Once the genotypes are known, there are many bioinformatics analysis tools that can compare individual genomes and find disease association of the genes and loci. The most important aspect of personal genomics is that it leads to the personal medicine where patients can take genotype specific drugs for medical treatments.</p><p>Personal genomics is not a single individual's vision or invention. Many researchers for decades anticipated this biological branch will eventually arrive with minimum cost of genotyping. Due to the advent of cheap and fast sequencers, full genome personal genomics is becoming a reality. However, there have been active early proponents of personal genomics projects such as <a title="George Church" href="http://en.wikipedia.org/wiki/George_Church">George Church</a> in Harvard Medical School.</p><p><a title="Genomics" href="http://en.wikipedia.org/wiki/Genomics">Genomics</a> used to mean academic research on consensus genomes which have been assembled from many different individuals of a particular species. The personal genomics changes this into customized bioinformatic discovery on individuals.</p><table summary="Contents" class="toc" id="toc"> <tbody> <tr> <td><br /> </td> </tr> </tbody></table> <p><a id="Use_of_personal_genomics_in_personalized_medicine" name="Use_of_personal_genomics_in_personalized_medicine"></a>&nbsp;</p>
<h2><span class="editsection"></span><span class="mw-headline">Use of personal genomics in personalized medicine</span></h2>
<p>Personalized medicine is the use of the information produced by personal genomics techniques when deciding what medical treatments are appropriate for a particular individual.</p>
<p><a id="Cost_of_sequencing_an_individual.E2.80.99s_genome" name="Cost_of_sequencing_an_individual.E2.80.99s_genome"></a></p>
<h2><span class="editsection"></span><span class="mw-headline">Cost of sequencing an individual&rsquo;s genome</span></h2>
<p>There is currently great interest in personal genomics. This is being fuelled by the rapid drop in the cost of sequencing a human genome. This drop in cost is due to the continual development of new, faster, cheaper DNA sequencing technologies such as <a title="DNA sequencing" href="http://en.wikipedia.org/wiki/DNA_sequencing#New_sequencing_methods">&quot;next generation DNA sequencing&quot;</a>.</p><p>The National Human Genome Research Institute, part of the U.S. National Institute of Health has set a target to be able to sequence a human-sized genome for US$100,000 by 2009 and US$1,000 by 2014<sup class="reference" id="cite_ref-0"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-0"><span>[</span>1<span>]</span></a></sup>. There is a widespread belief that within 10 years the cost of sequencing a human genome will fall to $1,000.</p><p>There are 6 billion base pairs in the diploid human genome. Statistical analysis reveals that a coverage of approximately ten times is required to get coverage of both alleles in 90% human genome from 25 base-pair reads with shotgun sequencing<sup class="reference" id="cite_ref-1"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-1"><span>[</span>2<span>]</span></a></sup>. This means a total of 60 billion base pairs that must be sequenced. An <a title="Applied Biosystems" href="http://en.wikipedia.org/wiki/Applied_Biosystems">ABI SOLiD</a>, <a title="Illumina (company)" href="http://en.wikipedia.org/wiki/Illumina_%28company%29">Illumina</a> or Helicos<sup class="reference" id="cite_ref-2"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-2"><span>[</span>3<span>]</span></a></sup> sequencing machine can sequence 2 to 10 billion base pairs in each $8,000 to $18,000 run. The purchase cost, personnel costs and data processing costs must also be taken into account. Sequencing a human genome therefore costs approximately $300,000 in 2008.</p>
<p>This cost is still too high for governments to introduce programs into health services to sequence the genomes of all individuals in a country. However, it may be viable when it falls below $1,000, and the cost of sequencing a human genome is dropping rapidly. For example, approximately 1 million babies are born in Canada each year. To sequence all of their genomes would cost approximately $1 billion per year, or just 1% of Canada&rsquo;s total healthcare budget.</p>
<p><a id="Comparative_genomics" name="Comparative_genomics"></a></p>
<h2><span class="editsection"></span><span class="mw-headline">Comparative genomics</span></h2>
<p><a title="Comparative genomics" href="http://en.wikipedia.org/wiki/Comparative_genomics">Comparative genomics</a> analysis is concerned with characterising the differences and similarities between whole genomes. It may be applied to both genomes from individuals from different species or individuals from the same species, generally at lower cost than sequencing from scratch. In personal genomics and personalized medicine, we are concerned with comparing the genomes of different humans. It is likely that many of the techniques which are developed in comparative genomic analysis will be useful in personal genomics and personalized medicine. This includes rare and common <a class="mw-redirect" title="Single nucleotide polymorphisms" href="http://en.wikipedia.org/wiki/Single_nucleotide_polymorphisms">Single nucleotide polymorphisms</a> (consisting substituting one base pair by another, for example CATGCCGG to CATGACGG), as well as insertion or deletion of one or many base pairs.</p>
<p><a id="Personalized_medicine_services_already_available" name="Personalized_medicine_services_already_available"></a></p>
<h2><span class="editsection"></span> <span class="mw-headline">Personalized medicine services already available</span></h2>
<p>At least four companies which offer genome-wide personal genomics services already exist. They are likely to be the first of many.</p>
<ul>
<li><a title="23andMe" href="http://en.wikipedia.org/wiki/23andMe">23andMe</a> sells mail order kits for <a title="SNP genotyping" href="http://en.wikipedia.org/wiki/SNP_genotyping">SNP genotyping</a><sup class="reference" id="cite_ref-3"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-3"><span>[</span>4<span>]</span></a></sup>. The $399 kit contains everything a patient needs to take their own saliva sample. The patient then mails the sample to 23andMe who carry out microarray analysis on it. This provides genotype information for about 600,000 SNPs. This information is used to estimate the genetic risk of the patient for over 80 diseases as well as ancestry analyses.</li>
</ul>
<ul>
<li><a title="DeCODE genetics" href="http://en.wikipedia.org/wiki/DeCODE_genetics">deCODEme.com</a><sup class="reference" id="cite_ref-4"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-4"><span>[</span>5<span>]</span></a></sup> offers a similar service to 23andMe, charging $985 to carry out an analysis of approximately 1 million SNPs and estimate the risk of 29 diseases.</li>
</ul>
<ul>
<li><a title="Navigenics" href="http://en.wikipedia.org/wiki/Navigenics">Navigenics</a><sup class="reference" id="cite_ref-5"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-5"><span>[</span>6<span>]</span></a></sup>, began offering SNP-based genomic risk assessments as of April 2008. Navigenics is medically focused and emphasizes a clinician's and genetic counselor's role in interpreting results. Currently over 20 disease are offered for $2500, with more in the works. <sup class="reference" id="cite_ref-6"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-6"><span>[</span>7<span>]</span></a></sup>. Navigenics uses Affymetrix Genome-Wide Human SNP Array 6.0 , which tests some 900,000 SNPs. <sup class="reference" id="cite_ref-7"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-7"><span>[</span>8<span>]</span></a></sup></li>
</ul>
<ul>
<li>Knome,<sup class="reference" id="cite_ref-8"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-8"><span>[</span>9<span>]</span></a></sup> provides whole genome (98% genome) sequencing services for $350,000. <sup class="reference" id="cite_ref-9"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-9"><span>[</span>10<span>]</span></a></sup><sup class="reference" id="cite_ref-10"><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_note-10"><span>[</span>11<span>]</span></a></sup></li> <li><a rel="nofollow" title="http://www.promethease.com" class="external text" href="http://www.promethease.com/">Promethease</a> is a free program that uses all the information generated by companies like those mentioned above to prepare a personal report based on analyzing personal DNA data in light of all the information in <a rel="nofollow" title="http://www.SNPedia.com" class="external text" href="http://www.snpedia.com/">SNPedia</a>, the wiki of SNP data from scientific and medical articles</li>
</ul>
<p><a id="Ethical_issues" name="Ethical_issues"></a></p>
<h2><span class="editsection"></span><span class="mw-headline">Ethical issues</span></h2>
<p>While personalized medicine will certainly be a great asset to healthcare, it opens up several ethical issues which will need to be thought about carefully. No doubt there will be a huge amount of debate concerning the ethics of personalised medicine in the coming years.</p>
<p><a title="Genetic discrimination" href="http://en.wikipedia.org/wiki/Genetic_discrimination">Genetic discrimination</a> is discriminating on the grounds of information obtained from an individual&rsquo;s genome. Genetic non-discrimination laws have been enacted in most US states and, at the federal level, by the <a title="Genetic Information Nondiscrimination Act" href="http://en.wikipedia.org/wiki/Genetic_Information_Nondiscrimination_Act">Genetic Information Nondiscrimination Act</a> (GINA).</p>
<p>The likelihood of an individual developing breast cancer is affected by which alleles they have of particular genes. Screening can reveal breast cancer in the early stages, allowing it to be successfully treated. 50% of breast cancers occur in the 12% of the population who are at greatest risk. This poses a very difficult question for health services: Is it ethical to deny somebody free screening for a disease if they are genetically at low risk of developing that disease?</p>
<p><a id="See_also" name="See_also"></a></p>
<h2><span class="editsection"></span><span class="mw-headline">See also</span></h2>
<ul>
<li><a title="Human genome map" href="http://en.wikipedia.org/wiki/Human_genome_map">Human genome map</a></li> <li><a class="mw-redirect" title="Single nucleotide polymorphism" href="http://en.wikipedia.org/wiki/Single_nucleotide_polymorphism">Single nucleotide polymorphism</a></li> <li><a title="Population genomics" href="http://en.wikipedia.org/wiki/Population_genomics">Population genomics</a></li> <li><a title="Bioinformatics" href="http://en.wikipedia.org/wiki/Bioinformatics">Bioinformatics</a></li> <li><a title="Genomics" href="http://en.wikipedia.org/wiki/Genomics">Genomics</a></li> <li><a title="Systems biology" href="http://en.wikipedia.org/wiki/Systems_biology">Systems biology</a></li> <li><a class="mw-redirect" title="Transcriptomics" href="http://en.wikipedia.org/wiki/Transcriptomics">Transcriptomics</a></li> <li><a class="mw-redirect" title="Omics" href="http://en.wikipedia.org/wiki/Omics">Omics</a></li>
</ul>
<p><a id="References" name="References"></a></p>
<div class="references-small">
<ol class="references">
<li id="cite_note-0"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-0">^</a></strong> <a rel="nofollow" title="http://news.nationalgeographic.com/news/2006/03/0307_060307_dna.html" class="external text" href="http://news.nationalgeographic.com/news/2006/03/0307_060307_dna.html">Coming Soon: Your Personal DNA Map?</a></li> <li id="cite_note-1"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-1">^</a></strong> <a rel="nofollow" title="http://www.nature.com/nature/journal/v452/n7189/extref/nature06884-s1.pdf" class="external text" href="http://www.nature.com/nature/journal/v452/n7189/extref/nature06884-s1.pdf">Table 4. Fractions of Heterozygotes as a function of Shotgun coverage(redundancy)</a></li> <li id="cite_note-2"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-2">^</a></strong> <a rel="nofollow" title="http://www.helicosbio.com/Technology/TrueSingleMoleculeSequencingtrade/tabid/64/Default.aspx" class="external text" href="http://www.helicosbio.com/Technology/TrueSingleMoleculeSequencingtrade/tabid/64/Default.aspx">True Single Molecule Sequencing (tSMS): Helicos BioSciences</a></li> <li id="cite_note-3"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-3">^</a></strong> <a rel="nofollow" title="https://www.23andme.com/ourservice/process/" class="external text" href="https://www.23andme.com/ourservice/process/">23andMe - Our Service: How the Process Works</a></li> <li id="cite_note-4"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-4">^</a></strong> <a rel="nofollow" title="http://www.decodeme.com/" class="external text" href="http://www.decodeme.com/">deCODEme, unlock your DNA</a></li> <li id="cite_note-5"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-5">^</a></strong> <a rel="nofollow" title="http://www.navigenics.com/" class="external text" href="http://www.navigenics.com/">Navigenics - Personalized genetic health services</a></li> <li id="cite_note-6"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-6">^</a></strong> <a rel="nofollow" title="http://content.nejm.org/cgi/content/full/358/2/105" class="external text" href="http://content.nejm.org/cgi/content/full/358/2/105">NEJM - Letting the Genome out of the Bottle - Will We Get Our Wish?</a></li> <li id="cite_note-7"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-7">^</a></strong> <a rel="nofollow" title="http://www.navigenics.com/healthcompass/HowProcessWorks/" class="external free" href="http://www.navigenics.com/healthcompass/HowProcessWorks/">http://www.navigenics.com/healthcompass/HowProcessWorks/</a></li> <li id="cite_note-8"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-8">^</a></strong> <a rel="nofollow" title="http://www.knome.com/" class="external text" href="http://www.knome.com/">Knome homepage</a></li> <li id="cite_note-9"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-9">^</a></strong> <a rel="nofollow" title="http://www.knome.com/FAQ/tabid/51818/Default.aspx" class="external text" href="http://www.knome.com/FAQ/tabid/51818/Default.aspx">Knome FAQ</a></li> <li id="cite_note-10"><strong><a title="" href="http://en.wikipedia.org/wiki/Personal_genomics#cite_ref-10">^</a></strong> <a rel="nofollow" title="http://www.nytimes.com/2008/03/04/health/research/04geno.html?_r=1&amp;adxnnl=1&amp;oref=slogin&amp;adxnnlx=1217772475-+MgNWGgVZmU6mG58Fc5HJQ" class="external text" href="http://www.nytimes.com/2008/03/04/health/research/04geno.html?_r=1&amp;adxnnl=1&amp;oref=slogin&amp;adxnnlx=1217772475-+MgNWGgVZmU6mG58Fc5HJQ">The DNA Age: Gene Map Becomes a Luxury Item, New York Times, March 2008</a></li>
</ol>
</div>
<h2><span class="editsection"></span><span class="mw-headline">External links</span></h2>
<ul>
<li><a relclass="nofollowexternal text" title="http://personalgenome.org" classrel="external textnofollow" href="http://personalgenome.org/">Personalgenome.org</a></li> <li><a relclass="nofollowexternal text" title="http://personalgenome.net" classrel="external textnofollow" href="http://personalgenome.net/">Personalgenome.net</a></li> <li><a relclass="nofollowexternal text" title="http://genomics.org" classrel="external textnofollow" href="../../">Genomics.org</a></li> <li><a relclass="nofollowexternal text" title="http://www.personomics.wordpress.com" classrel="external textnofollow" href="http://www.personomics.wordpress.com/">Personal Genomics Blog</a></li> <li><a relclass="nofollowexternal text" title="http://www.snpedia.com" classrel="external textnofollow" href="http://www.snpedia.com/">SNPedia</a></li> <li>[http://psychogenomics.org Psychogenomics.org]</li>
</ul>
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