Table 1.

Production of pigmented chimeras from MES1 cells

Experiment	Passage- days of culture	Embryos injected, n	Embryos scored, n	Pigmented embryos, n
1.	27–205	78	34	1
2.	28–225	96	33	1
3.	31–234	69	60	3
4.	37–310	100	58	5
5.	36–252	57	19	1
6.	40–320	44	15	1
7.	66–396	43	7	1
8.	66–397	64	37	2
	Total	551	263 (48%)*	15 (6%)†

^*Proportion of embryos injected that were alive at the time of scoring for chimerism by pigmentation beginning at day 3: number scored/number injected × 100. 

^†Proportion of embryos scored for pigmentation that showed wild-type pigment cells: number pigmented/number scored × 100.