Tag Archives: Y-STRs

Genetic Geneology: Is Sarah Yarborough’s Killer a Mayflower Descendant?

In The Double Helix and the Law of Evidence, I remarked that “[s]urname prediction is a concept that has yet to be implemented in forensic science . . . ” (1, p. 211). Now, cold-case detectives investigating the 1991 rape and strangulation of a 16-year old girl in Seattle are looking for “a distant relative of Edward and Samuel Fuller, who crossed the Atlantic on the Mayflower in 1620 [and who] might even share their last name” (2).

Sarah Yarborough left home to take part in a dance-team competition one morning in December. She never returned. Six people had seen a man in his 20s, with shoulder-length blond hair, a trench coat and dark pants speaking with her or leaving a brushy area where her body was found. In the succeeding months, more than 3,000 tips poured in. DNA analysis excluded some suspects, but trawling offender DNA databases for an exact match produced no leads, and the killer remains unidentified.

Yet, other databases can be searched. “Genetic geneology databases” (3, p. 384) that use Y-STR haplotypes of interest in anthropology are growing in popularity, and some are available on the web. At the suggestion of a scientist at the state crime laboratory, police turned to Identifinders of Huntington Beach, California. Presumably, the firm combed through the online databases to arrive at its conclusion that “there’s a good chance the killer’s last name is or was Fuller” (4) because “the killer is a descendant of Robert Fuller, who arrived in Salem, Mass., in 1630. Fuller was not himself on the Mayflower, but he was related to three passengers: Edward Fuller, as well as Edward Fuller’s brother, Samuel, and 12-year-old son” (2).

The value (and accuracy) of this surmise remains to be seen. None of the tips the police received involve a Fuller (2), and many Fullers had nothing to do with that historic voyage. Moreover, the Mayflower Fullers may be multitudinous. After all, “there are tens of millions of people descended from the 102 passengers and about 25 crew members who arrived on the Mayflower . . .” (2).

Acknowledgment: Thanks to Gene Johnson for telling me about the Yarborough case.


  1. David H. Kaye, The Double Helix and the Law of Evidence (2010).
  2. Gene Johnson, Awkward Twist over DNA Link in Teen’s Slaying, Seattle Times, Jan. 12, 2012
  3. John M. Butler, Advanced Topics in Forensic DNA Typing: Methodology (2011).
  4. Gene Johnson, Mayflower Relative Sought in ’91 Wash. Killing, Seattle Post-Intelligencer, Jan. 11, 2012

Cross-posted to Forensic Science, Statistics, and the Law