Tuesday, 1 January 2013

Y-chromosome and mtDNA of Henri IV

A recent paper had determined the Y-chromosome haplotype of Louis XVI of France from a handkerchief preserving his blood after his execution. A new study looks at the mummified head of Henri IV, the first Bourbon King of France. Even though only a limited number of Y-STRs were successfully typed, they match those of Louis XVI, who belonged to the not-so-frequent-anymore haplogroup G2a. So, while we cannot be entirely sure that the two Y-chromosomes were related in a genealogical time frame, the evidence is consistent with their known genealogical relationship and with the attribution of the two samples (mummified head/blood) to the respective kings.

Also of interest, Henri IV's mtDNA haplotype:
The majority of the clones generated show an U5b* mtDNA haplotype defined by three nucleotide changes at positions 16239T 16270T 16311C (see Supplementary material). The three HVR1 diagnostic positions were confirmed in two different amplifications of the L16185-H16378 HVR1 fragment, proving that the results are reproducible. This mtDNA haplotype is present so far in one single individual from France (originally published in [10]) in an in-house database of 22,807 published European sequences, and it is absent in all people involved in the laboratory analysis.
 If I followed the trail of ancestry correctly, this matrilineage leads all the way to a Tochter von Egisheim in the 11th century.

Forensic Science International Available online 30 December 2012

Genetic comparison of the head of Henri IV and the presumptive blood from Louis XVI (both Kings of France)

Philippe Charlier et al.

A mummified head was identified in 2010 as belonging to Henri IV, King of France. A putative blood sample from the King Louis XVI preserved into a pyrographically decorated gourd was analyzed in 2011. Both kings are in a direct male-line descent, separated by seven generations. We have retrieved the hypervariable region 1 of the mitochondrial DNA as well as a partial Y-chromosome profile from Henri IV. Five STR loci match the alleles found in Louis XVI, while another locus shows an allele that is just one mutation step apart. Taking into consideration that the partial Y-chromosome profile is extremely rare in modern human databases, we concluded that both males could be paternally related. The likelihood ratio of the two samples belonging to males separated by seven generations (as opposed to unrelated males) was estimated as 246.3, with a 95% confidence interval between 44.2 and 9729. Historically speaking, this forensic DNA data would confirm the identity of the previous Louis XVI sample, and give another positive argument for the authenticity of the head of Henri IV.


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