Human septins have been divided into four groups, named after the most important member of each: SEPT2, SEPT3, SEPT6 and SEPT7 (in bold). These are known as the Kinoshita’s groups.

To encompass septins from other organisms, these groups have been reorganized and other groups have been created (Pan et al. 2007, Auxier et al. 2019):

• Group 1A: Human SEPT3 group, including also CDC10 from yeast;
• Group 1B: Human SEPT6 group;
• Group 2A: Not present in humans, but includes CDC3 from yeast;
• Group 2B: Human SEPT2 and SEPT7 groups;
• Group 3: Not present in humans, but includes CDC11 from yeast;
• Group 4: Not present in humans, but includes CDC12 from yeast;
• Group 5: Not present in humans; the most ancestral group.