Length 3, number of unique variants is 7.
crc	[clc,clc,crc,crc]
ctt	[ctt,ctt,ctt,ctt]
crr	[cll,crr,crr,cll]
ctc	[ctc,ctc,ctc,ctc]
ccr	[ccl,ccr,ccr,ccl]
cct	[cct,cct,cct,cct]
ctr	[ctl,ctr,ctr,ctl]