犹太人没有真正的基因标定。祖上信犹太教，后代就成为犹太人后裔

Marx和Lenin的所谓是犹太人，都是因为祖先有某一支有过信教的犹太人。

 

至于他们本人，Marx父母在他出生前就成为了基督教徒。所以，他根本不能被称为犹太人。“Marx's family was originally non-religious Jewish but had converted formally to Christianity before his birth.”

 

至于Lenin，他更是坚定的anti-nationalist

https://www.quora.com/Is-it-true-that-Lenin-said-An-intelligent-Russian-is-almost-always-a-Jew-or-someone-with-Jewish-blood-in-his-veins