How did they get Copernicus genes?
It is not certain that they got his genes but they did dig up what may be his skeleton from the parish in which he was a priest and they did recover hairs from between the pages of one of his books which had been looted by Swedes during the Deluge. The genetic analysis of these remains did not however prove EM Wave's claim that:
there's been a genetic study showing that Copernicus had Germanic roots, not Slavic roots.
The result of the EMPOP database search is interesting from the perspective of Copernicus' maternal lineage. His maternal ancestors may have originated from Silesia, and can thus be of German descent. Copernicus' grandmother, Catherina, was first married to Heinrich Peckau, who was a member of the council of Thorun. After Heinrich's death, Catherina was married to a trader and famous enemy of the Teutonic Knights-Lucas Watzenrode. The same haplotype has been found in individuals from many countries, including Austria, Germany, Poland, and the Czech Republic. It is interesting to note that Copernicus' paternal ancestors may also have originated from Silesia. Copernicus' father, also named Nicolaus, was a known trader in Cracow. He moved to Thorun ≈1458 where he married Barbara Watzenrode. Nicolaus Copernicus was their youngest son. The Y-chromosome data that we obtained will be useful if reference samples from some of Copernicus' relatives along the paternal lineage are ever collected.
ncbi.nlm.nih.gov/pmc/articles/PMC2718376/
They wouldn't be letting them into the armed forces if they didn't want them to be Israelis.
Non-Jewish Arabs with Israeli citizenship, save for a few Bedouins and Druze, are not allowed to serve in the Israeli armed forces.