Our studies confirm those based on other genetic markers that suggest that the admixture of the Jewish population with the surrounding European population has been relatively meager
(booksc.org)https://booksc.org/book/15688204/3d6d68Full text:
Ashkenazi Jews seem to have migrated to the
Rhineland by the eighth century (7). The existence
of ‘‘Jewish diseases’’ such as Tay-Sachs disease,
Gaucher disease and Niemann-Pick disease in this
population, diseases that are relatively rare in the
non-Jewish population, implies a considerable
degree of genetic isolation. Moreover, a number of
genetic markers, particularly those in the HLA
system, suggest that the extent of genetic exchange with surrounding European populations
has been meager (8)
From another study:
Like most Eurasians, Yiddish speaker genomes are a medley of three major components:
Mediterranean (𝑋𝑋�=52%), Southwest Asian (𝑋𝑋�=24%), and Northern European (𝑋𝑋�=16%)
(Figure 2A), although, like the ancient pre-Scythian, they also exhibit a small and
consistent Subsaharan African component (𝑋𝑋�~2%), in general agreement with Moorjani
et al. (2011)
source:
https://booksc.org/book/50942854/ff8704 
