{TAIL ~ Homology} or identity can be determined by comparing a position in each sequence which may be aligned for purposes of {HEAD ~ comparison} 
{ TAIL ~ Homology } or identity can be determined by comparing a position in each sequence which may be aligned for purposes of { HEAD ~ comparison }
TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD