This objection is easily overcome Not only do you test the subject, you also test their parent, sibling, nephew, etc to prove that the original kit was not contaminated. -----Original Message----- From: McDonald, J Douglas <jdmcdona@illinois.edu> To: genealogy-dna@rootsweb.com <genealogy-dna@rootsweb.com> Cc: odoniv@yahoo.com <odoniv@yahoo.com>; Wjhonson <wjhonson@aol.com> Sent: Tue, Nov 27, 2018 6:21 pm Subject: [DNA] Re: Use of familial search by law enforcement Autosomal DNA tests, of the 700,000 marker sort used by the commerical companies, can never result in a false positive ***IF*** 1) no identical twin exists (there are tests that can tell them apart) 2) both samples are uncontaminated But for criminal purposes the 2nd is very very frequently not true. If a sample is contaminated, the chip tests can be useless. A high coverage (100x) Illumina full sequence of both samples would be better. Better yet would be a 100x long read (10xgenomics or the lastest claimed 99% accurate PacBio) full sequence, of the possibly contaminated sample. CODIS tests are just not extensive enough to be reliable for contaminated samples. If the CODIS (STR) idea had say 200 markers instead of the CODIS number (12???) then it would be better. Without that, I as a juror would be very leery unless there was clearly no possibility of contamination. Doug McDonald ________________________________ From: Wjhonson via GENEALOGY-DNA <genealogy-dna@rootsweb.com> Subject: [DNA] Re: Use of familial search by law enforcement The entire basis of this thread is to counter the outrageous claim that the type of *autosomal* DNA which is loaded to gedmatch could *EVER* result in a false positive. It can *never* result in a false positive.  Autosomal DNA is so precise it can tell parent from child, sibling from sibling, cousin from cousin.  There is no such thing as a false positive. _______________________________________________ Email preferences: http://bit.ly/rootswebpref Unsubscribe https://lists.rootsweb.com/postorius/lists/genealogy-dna@rootsweb.com Privacy Statement: https://ancstry.me/2JWBOdY Terms and Conditions: https://ancstry.me/2HDBym9 Rootsweb Blog: http://rootsweb.blog RootsWeb is funded and supported by Ancestry.com and our loyal RootsWeb community

That may be a scientific solution, but it's not a legal one. Wjhonson via GENEALOGY-DNA wrote: > This objection is easily overcome > Not only do you test the subject, you also test their parent, sibling, nephew, etc to prove that the original kit was not contaminated. > >

That's absurd. We're talking samples which are unknown ... you know, the unknown rapist. There's no problem with the suspect's DNA once a search warrant for it is issued. Doug -----Original Message----- From: Wjhonson via GENEALOGY-DNA <genealogy-dna@rootsweb.com> Sent: Tuesday, November 27, 2018 8:25 PM To: genealogy-dna@rootsweb.com Cc: odoniv@yahoo.com; Wjhonson <wjhonson@aol.com> Subject: [DNA] Re: Use of familial search by law enforcement This objection is easily overcome Not only do you test the subject, you also test their parent, sibling, nephew, etc to prove that the original kit was not contaminated. al RootsWeb community