Turi King, the Leicester geneticist leading the DNA analysis, worked with four living male-line descendants of the Somerset branch. She sequenced their Y-chromosome haplotypes and found that they matched one another — confirming that the documented male lineage was intact within that group. She then compared those sequences to the Y-chromosome DNA extracted from the skeleton.
They did not match.
The Y-chromosome DNA from the skeleton differed from that of the four Somerset-line comparators. This meant that the paternal line between the skeleton and the Somerset descendants was broken at some point — that somewhere between Richard III and the Somerset line, the documented father-son succession had not reflected the actual biological relationship.
This type of discrepancy is known as a false paternity event, or non-paternity event: a situation in which a child recorded as the son of one man was biologically the son of another. Such events occur in all human populations; studies have estimated rates of roughly one to two percent per generation. In a chain of 19 generations — the documented number of generations between Richard III and the Somerset-line descendants — one or more such events would be statistically plausible.
The researchers also tested a sample provided by Patrice de Warren, who claimed descent through a male line from Geoffrey, Count of Anjou, an ancestor shared with the Plantagenet line that predated Richard III. His Y chromosome matched neither Richard’s skeleton nor the Somerset-line comparators. This suggested that there was at least one additional break in the extended male lineage beyond the one between Richard and the Somerset line, though the test could not locate the break more precisely.