Temperature Sensitive Mutants - This type of mutants survive at one temperature and die when exposed to another temperature. Most temperature sensitive mutants are sensitive to heat. These mutants arise due to mutations in heat shock proteins or chaperone genes.

A mutation can occur in nuclear genes (Nuclear mutation) or in chloroplasts, mitochondria or cytoplasmic genes (cytoplasmic mutations). Nuclear mutations can be autosomal mutations (occur in autosomes) or sex linked mutations (occur in allosomes) or holandric mutations (occur in sex chromosomes present in one sex individual, e.g. Y-chromosome).