Non Genetic Data. The What and Why s of

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1 Non Genetic Data: The What and Why s of Melody Josserand, M.S. Forensic Analyst II / CODIS Analyst UNTCHI Non Genetic Data How we use knowledge of DNA to make identifications Why DNA is often not enough by itself How metadata can assist investigators and the DNA lab Making Associations It is our goal here at the UNT Center for Human ID to aid in giving identities to the thousands of unidentified remains in Texas and around the country, and in so doing to aid in criminal i linvestigations More importantly, our work here gives answers to the many families whose lives have been affected by the unexplained disappearance of a loved one 1

2 Nuclear DNA Mitochondrial DNA Inherited maternally Passed directly from mothersto to children (both male and female children) Y STR s STR s found on the Y chromosome Specific to males Passed directly from fathers to male children Y chromosome 2

3 Inheritance Why is knowing about inheritance useful? By comparing family reference samples to remains samples, we can associate remains to families who aremissing loved edones Knowledge of inheritance allows us to use the appropriate technology on each reference sample Knowledge of inheritance allows us to collect appropriate (useful) reference samples Inheritance AB CD BC Children and parents will share alleles at each location in a DNA profile Shared Markers AB CD AB CD BC BD AB CD AB CD AC AD Siblings may or may not share alleles 3

4 Shared Markers Maternal siblings will share their mitochondrial DNA sequence Appropriate Reference Samples First Order Relatives: Mom, Dad, Children STR s, mito, Y STR s First Order Relatives: Siblings (plural!) STR s, mito, Y STR s Second Order Relatives: Grandparents, Grandkids, Aunts, Uncles Mito, Y STR s, STR s The general rule for FRS s is: The More, The Merrier!! Appropriate Reference Samples Hospital Tissue Biopsies or Pathological Specimens Baby Teeth Personal Effects: Toothbrushes, Razors, Hairbrushes Submit with FRS s for comparison 4

5 CODIS Indices Convicted Offender Forensic Casework Relatives of Missing Person Missing Person Unidentified Human Remains Database Searching Remains profiles developed at our laboratory from bones, tissue, hair, etc. are entered into our local CODIS database (LDIS) Family reference sample and direct reference sampleprofiles profiles developed at our laboratory from buccal swabs or blood are entered into LDIS These profiles are searched against each other, and potential associations are evaluated to determine if they are valid Database Searching An unidentified remains match to a biological child Notice that the profiles share a marker at each locus 5

6 Database Searching Sibling match to Unidentified Remains Notice these 2 loci no markers in common This is why parents and children are more valuable in establishing identity Database Searching Sibling match to Unidentified Remains The mtdna profile is a direct match between siblings Spurious Hits Oftentimes when searching unidentified remains or reference samples in a database, many spurious hits occur 6

7 Spurious Hits 307 Spurious Hits Wading through all those false associations to try to find the real one(s) is a known cause of Spurious Hits Oftentimes when searching unidentified remains or reference samples in a database, many spurious hits occur Each of these associations must be individually ruled to be true or false based on 7

8 Spurious Hits We ve done the science; now we need your help to determine whichof these associations, if any, indicate true relationships! Data about data For our purposes, it includes data about: Unidentified Remains When were the remains found? Where were they found? Had they been there long? Male or Female? Short or Tall? Race? Scars, Marks, or Tatoos? Medical Anomalies? Full or Partial Skeleton? For UHR s, submission forms include sections for many types of metadata 8

9 If this information is not readily available, the forensic anthropologists here at UNT are ready to help fill in the blanks Data about data For our purposes, it includes data about: Missing Persons When was the missing person last seen? Where? Male or Female? Short or Tall? Race? Scars, Marks, or Tatoos? Medical Anomalies? 9

10 For FRS s, submission forms include a page for a description of the missing person 10

11 These forms are YOUR forms, developed for you to collect information about these cases You may already have solved a case when you fill out these forms and submit them to the lab with the remains or reference samples if all the information is there, filtering out spurious associations takes less time and allows us to narrow in on good associations more quickly If there is limited or no metadata submitted with each case, our next resource for judging the authenticity of any associations is to contact the submitting agency. Oftentimes there is quite a bit of work involved (by us here in the lab and by the investigator) in ruling out false hits. Also, contacting the submitting agency can result in false hope. Gathering good metadata at the front end of a case submission can save lots of time and wasted hope! 11

12 Database Searching National searches occur once monthly, and include all sample profiles uploaded into the database. If a specimen does not hit on another profile immediately don t lose heart! The sample profiles remain in each of these databases for continued searching in hopes of making identifications in the future Database Searching in the Future Future iterations of CODIS software promise to bring the ability to upload some metadata into NDIS. For us in the lab, this means any data we can capture now will only aid in narrowing our search criteria in the future. In Conclusion Provide as much metadata as possible when submitting cases to your DNA labs Good sources for metadata are ME s reports, crime scene reports, and anthropology reports Submit more than one reference sample for missing persons cases When in doubt about what to send call us!

13 Contact Information mfarrar@hsc.unt.edu 13