Forensic DNA Identification from Human Remains Submerged in Water

1. Forensic DNA Identification from Human Remains Submerged in Water By Cheryl M. Lowe April 29, 2009

2. Background There are many incidences where human remains end up in water What are the distinguishing features of human remains found in water? Is there a difference between salt water and fresh water in regard to DNA preservation?

3. Background There are many factors that affect the integrity of DNA evidence from remains found in water Limited research so far on how long DNA can be preserved in water

4. Definitions Seawater = water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5%, or 35 parts per thousand The density of surface seawater ranges from about 1020 to 1029�kg�m-3, depending on the temperature and salinity Fresh water = naturally occurring water on the surface such as bogs, ponds, lakes, rivers and streams and underground in aquifers and underground rivers Low concentrations of dissolved salts coastal areas freshwater may contain significant concentrations of salts derived from the sea if windy conditions have lifted drops of seawater into the clouds

5. Total Molal Composition of Seawater (Salinity = 35) Component Concentration (mol/kg) H2O 53.6 Cl- 0.546 Na+ 0.469 Mg2+ 0.0528 SO42- 0.0282 Ca2+ 0.0103 K+ 0.0102 CT 0.00206 Br- 0.000844 BT 0.000416 Sr2+ 0.000091 F- 0.000068

6. Remains Submerged in Water Favorable conditions for adipocere Increased saponification due to exposure to excess of water Cells absorb water until rupture, then release fatty contents that are then hydrolyzed and hydrogenated Adipocere is common in remains found in bathtubs, ponds, lakes, oceans Bloating, skin slippage, wrinkling of hands and feet common

7. Remains Submerged in Water Tissue loss from: Effects of the water current Chemical composition of water Industrial waste water Predation by insects, marine animals, fish

8. Body at 4 weeks

9. Body at 7 weeks

10. Body at 12 weeks

12. Case Example � Fresh Water Decomposed remains found in a dam on the Seine River after 3 years Successful recovery of DNA profiles using Profiler Plus kit from bone (10 STR loci and amelogenin) No results from saponified sternocleidomastoid muscle

13. Case Example � Fresh Water

14. Case Example � Fresh Water

15. Case Example � Salt Water Skeletonized remains found in 2 rubber boots in March 2005, 145m deep in the Southern Australian coast (Great Australian Bight) DNA analyses on reference samples from relatives of fishermen who had disappeared in the area Victim identified with Profiler Plus kit as a 52 year old prawn fisherman, swept off of boat about 10 years earlier

16. Case Example � Salt Water DNA stability maintained by low light conditions, cold temperatures, alkaline pH of the ocean floor (pH was between 7.5 and 8.5)

17. Case Example � Salt Water Remains found relatively preserved within rubber boots Wedges of bone from distal ends of each tibia were submitted for DNA analysis Homicide with dismemberment was considered as a possible scenario Possibility of drifting of remains along the ocean floor�could have come from coastal areas

18. DNA Profiles Obtained

19. DNA Stability in Water DNA integrity can be preserved under the following conditions: High mineral content of water: high amounts of calcium, magnesium, carbonates, sulfides, sulfates Anaerobic environment: limits oxidative damage of DNA, as well as bacterial and fungal growth Neutral pH: around 6.1 to 6.9, buffered from presence of carbonates Low oxygen tension

20. DNA Stability in Water From 1984 to 1987, there were 177 ancient individuals of all ages recovered from Windover pond, Florida Atlantic Coastal Ridge Intact crania with pieces of preserved brain matter Pond possessed favorable conditions for DNA preservation; preliminary Southern blot showed traces of human DNA

21. Discussion Water can preserve DNA evidence in most cases The most important factor in the recovery of DNA evidence from submerged remains seems to be time However, it can sometimes complicate data�especially in mass disaster investigations (Southeast Asian tsunami)

22. Conclusions DNA identification by itself is not fully reliable from human remains found in aqueous environments Important for other metadata to be incorporated, such as dental identification, anthropological studies Further research needs to be done

23. Bibliography Crainic K, Paraire F, Leterreux M, Durigon M, Mazancourt P. Skeletal remains presumed submerged in water for three years identified using PCR-STR analysis. J Forensic Sci, Sept. 2002, Vol. 47, No. 5. (1-3) Byard RW, Both K, Simpson E. The identification of submerged skeletonized remains. American Journal of Forensic Medicine and Pathology. March 2008, Vol. 29, No. 1, pages 69-71. O�Brien TG, Kuehner AC. Waxing grave about adipocere: soft tissue change in aquatic context. J Forensic Sci, March 2007, Vol. 52, No. 2, 294-301. Herrmann Bernd, Susanne Hummel. Ancient DNA: Recovery and Analysis of Genetic Material from Paleontological, Archaeological, Museum, Medical, and Forensic Specimens. Springer, 1994. Pages 105-106. Graw M, Weisser HJ, Lutz S. DNA typing of human remains found in damp environments. Forensic Science International 113 (2000) 91-95. Pacher J, Cameron J. Submersion cases: a retrospective study 1988-1990, Med. Sci. Law 32 (1992) 15-17. Swann H, Spafford N. Body salt and water changes during fresh and sea water drowning, Texas Rep. Biol. Med. 9 (1951) 350-384.

24. Questions?