↓from,to→		A	C	G	T	total
A	0.999815	0.000060	0.000079	0.000023	20401300
C	0.000064	0.999867	0.000029	0.000090	23058315
G	0.000088	0.000021	0.999850	0.000061	23135703
T	0.000013	0.000067	0.000059	0.999805	20243971