{"id":478,"date":"2008-10-01T18:16:56","date_gmt":"2008-10-01T22:16:56","guid":{"rendered":"https:\/\/www.therestlesssleep.com\/?p=478"},"modified":"2009-12-07T15:32:09","modified_gmt":"2009-12-07T19:32:09","slug":"touch-dna-or-low-copy-number-lcn","status":"publish","type":"post","link":"https:\/\/www.therestlesssleep.com\/?p=478","title":{"rendered":"Touch DNA or Low Copy Number (LCN)?"},"content":{"rendered":"<p><a href=\"https:\/\/www.therestlesssleep.com\/wp-content\/uploads\/2008\/10\/lcn.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft size-full wp-image-479\" title=\"lcn\" src=\"https:\/\/www.therestlesssleep.com\/wp-content\/uploads\/2008\/10\/lcn.jpg\" alt=\"\" width=\"226\" height=\"170\" \/><\/a>There&#8217;s been a rash of articles about &#8220;touch DNA&#8221; this year, which is, as far as I can tell, another name for what is already known as Low Copy Number (LCN). \u00a0LCN is a method of getting DNA profiles from very small samples, like a fingerprint (hence the alternative name &#8220;touch DNA&#8221;) and it was developed in the UK. Although one article I found stated that it&#8217;s not the same, it looks like that&#8217;s not correct. Perhaps a forensic scientist will email or comment with a definitive answer.<\/p>\n<p>While I was researching this I saw that there was a problem last year in the UK with a case with LCN evidence, and using LCN evidence was suspended for a period. However, according to an <a href=\"http:\/\/news.bbc.co.uk\/2\/hi\/uk_news\/7341251.stm\">April 11 BBC article<\/a>, which gives an excellent overview of how LCN analysis is done, the government commissioned a study which concluded that the method was sound. \u00a0A quote from\u00a0Professor Brian Caddy: \u00a0<em>\u201cThe technique&#8230; is scientifically robust and appropriate for use in police investigations.\u201d\u00a0<\/em><\/p>\n<p>I also came across other criticisms of the process, but I couldn&#8217;t get access to one intriguing article at nature.com:\u00a0<strong>LCN DNA: proof beyond reasonable doubt?, <\/strong>by<strong>\u00a0<span style=\"font-weight: normal;\">Carole McCartney.\u00a0A debate has evolved in response to this piece, but you have to have an account to read the article and the responses to it. \u00a0<\/span><\/strong><\/p>\n<p>When I wrote my book the Office of the Chief Medical Examiner in New York was not equipped to do LCN analysis, but I heard that now they can. \u00a0In fact, I&#8217;ll bet that&#8217;s why this name &#8220;touch DNA&#8221; is making the rounds. \u00a0It used to be that you had to send samples to the UK (or Canada, too I believe) to get\u00a0LCN analysis. \u00a0But now that several commercial labs in the U.S. can do it, they&#8217;re probably trying to brand the process with this other name, and they sent out a bunch of press releases which resulted in a wave of articles about &#8220;touch DNA.&#8221; \u00a0Just a guess. \u00a0(If it turns out that LCN and touch DNA are two entirely different methods of analyzing small DNA samples my guess is wrong.)<\/p>\n<p>The picture above is from the BBC piece I cited and linked to.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>There&#8217;s been a rash of articles about &#8220;touch DNA&#8221; this year, which is, as far as I can tell, another name for what is already known as Low Copy Number (LCN). \u00a0LCN is a method of getting DNA profiles from very small samples, like a fingerprint (hence the alternative name &#8220;touch DNA&#8221;) and it was [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","footnotes":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false,"jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false}}},"categories":[17],"tags":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/piV6s-7I","_links":{"self":[{"href":"https:\/\/www.therestlesssleep.com\/index.php?rest_route=\/wp\/v2\/posts\/478"}],"collection":[{"href":"https:\/\/www.therestlesssleep.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.therestlesssleep.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.therestlesssleep.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.therestlesssleep.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=478"}],"version-history":[{"count":6,"href":"https:\/\/www.therestlesssleep.com\/index.php?rest_route=\/wp\/v2\/posts\/478\/revisions"}],"predecessor-version":[{"id":537,"href":"https:\/\/www.therestlesssleep.com\/index.php?rest_route=\/wp\/v2\/posts\/478\/revisions\/537"}],"wp:attachment":[{"href":"https:\/\/www.therestlesssleep.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=478"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.therestlesssleep.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=478"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.therestlesssleep.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=478"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}