新生 しんせい突然 とつぜん変異 へんいではありませんでした
shinseitotsuzenhen'idewārimasendeshita

Noun
Desu Copula

The polite, past negative form of 新生突然変異

1. It was not a new mutation.; It wasn't a new mutation.

Past/Perfective
Negative
Polite
Formal Register
Genetics