Table 2.

p53 gene mutations detected by the GeneChip p53 assay and not detected by dideoxynucleotide sequencing

Sample	p53 gene mutation*	p53 GeneChip score†	Confirmed‡
Mutation missed on first sequencing (gel-reader error)
778	g → t, intron 8	14	ND
901	GAG  → TAG at 294	23	Yes
938	CAG  → TAG at 165	14	ND
971	a → g, intron 6	32	Yes
1,105	CGA  → TGA at 213	15	Yes
1,133	TGT  → TTT at 277	17	ND
Mutation not visible on first sequencing gel but present on repeat gel
847	ATC  → TTC at 195	24/20	Yes
1174	GCC  → CCC at 159	17/17	Yes
Mutation not visible on first or on repeat sequencing gels
864	CCT  → CTT at 190	26/24	Yes
1,049	ACC  → ATC at 253	15/12	Yes
1,052	TAT  → TGT at 220	13/17	Yes
1,113	GAC  → GTC at 208	14/13	Yes
Mutation outside of conserved regions evaluated (not by  dideoxynucleotide sequencing)
1,011	GAG  → TAG at 339	15	Yes
1,102	GGG  → TGG at 334	32	Yes
Mutation present in intron 8 and not included on sequencing gel
1,023	a → t, intron 8	31	ND
Mutation not present on sequencing gel or on repeat GeneChip  analysis
1,318	GGC  → GGT at 154	13/0	ND

^*p53 mutation gene mutation at given codon determined by the GeneChip p53 assay. 

^†Samples 847, 864, 1,049, 1,052, 1,113, 1,174, and 1,318 were analyzed twice from two different PCR amplifications. 

^‡Mutation confirmed by hybridization of mutant specific oligonucleotide probe to tumor DNA and not to normal DNA. ND, not done.