Table 2.

Percent H2A.Z asymmetry with respect to the self-renewal pattern regulation of diverse cultured cell types.

Cell Type	Promoted Self-Renewal Patterna				pb
	(basis)	ASYM	(basis)	SYM
p53-MEFsc	(p53 wt)	32	(p53 null)	7	< 0.024
pc-MEFsd	(p53 wt)	7	(p53 KO)	<1	< 0.009
immMEFse	n/af	n/a	(immort)	<1	n/a
HFSCs	(−Xng)	20	Ndh	nd	n/a
hSATs	(−Xn)	12	(+Xn)	4	< 0.004

^aListed are the observed percentages of pH3-positive prophase nuclei showing H2A.Z asymmetry for the indicated cell types under conditions that promote either asymmetric self-renewal and non-random chromosome segregation (ASYM) or symmetric self-renewal and random segregation (SYM).

^bStatistical confidence, determined by the two-tailed Fisher's exact test, for the differences in percentage between states promoting asymmetric self-renewal versus symmetric self-renewal.

^cWild-type p53-inducible MEFs and p53-null MEFs grown in ZnCl₂-supplemented medium, corresponding to micro-array Comparison 1 (See also Fig. 1).

^dPre-crises mouse embryonic fibroblasts from mice with a wild-type p53 genotype were compared to analogous cells derived from mice with a p53 gene knockout (KO) after 17 and 12 population doublings in culture, respectively. (The p53 wt cells had a transgenic KO of the cdkn1A gene.)

^eThe same strain of p53 wt/cdkn1A KO MEFs was evaluated after spontaneous immortalization and culture for a total of 50 population doublings.

^fn/a = not applicable

^gXn = xanthine

^hnd = not done