The National Human Genome Research Institute says that strawberries have seven unique chromosomes. However, through human breeding, strawberries are capable of having many different chromosomal combinations by variety.
Strawberry varieties all exhibit their own polyploidy, which means the number of times their unique chromosomes are duplicated. For instance, diploid strawberries duplicate their seven chromosomes twice for a total of 14 chromosomes. Tetraploid strawberries duplicate their chromosomes four times for 28 total, while hexaploid strawberries duplicate six times for 42 total chromosomes. Strawberries can also be octoploid with eight sets or decaploid for ten sets. Strawberries with more duplication are larger and produce more berries per plant.