To Whom This May Concern:
There is a yDNA haplogroup associated with the patriline of R' Yssachar Hildesheim. For those interested in using the haplogroup to establish a descent from this lineage, please see the document in the https://www.geni.com/projects/Rabbinical-Lineages-yDNA-and-Haplogro..., available through the photos and documents page.
