At the moment I'm ok with accepting the status quo and have not deeply looked into it....
....BUT....
....Marxists have historically treated science as an ideology, because they were influenced by Fredrich Engels views on applying the principles of Marxist philosophy (dialectical materialism) to natural science. very crudely, "genetics" was percieved to represent some aspect of "class ideology" in conflict with Marxism by promoting theories of innate inequalities amongst humans as biologically determined rather than a product of socio-economic class. There are also some potentially theological implications to genetics if you treat the combination of genetic material and traits as "accidental" rather than a product of a larger process of the evolution of matter from simple to more complex forms (i.e. what or who "created" it that way?).
So the exact deatils on the mechanism by which "evolution" took place do conflict with Marxist ideology.Overall, they favoured Lemarckianism (the inheritiability of aquired traits) over Mandellian genetics (inheritence by "genetic" or biologically innate traits). Mandellian Genetics was also used as part of Nazi Ideology and Eugencis so it was considered "fascist" science in the USSR under Stalin. They gave offical support to Lysenkoism but it was a disaster as ideological reasons took precedence over nuaunce and evidence and set back Soviet biologists many decades. There were attempts to incorporate genetics into soviet science but they didn't get much approval for all of the reasons specified above, so its not completely impossible to reconcile scientific evidence and marxist ideology on this.
The one big plus though is that the "primordial soup" theory of the origins of life or abiogenisis (origin of life from inorganic matter) was theorised by a Soviet Scientist (Alexander Oparin) in the 1920s. that is on ideologically safer territory about the dialectical laws of motion and a "qualitative leap" from chemistry and biology in the evolution of the organisation of matter.
If your confused, don't worry; that's the dialectics rotting your brain into Communist Party approved mush.