Table 2.

Laboratory Abnormalities in TTD- or XP-Affected Individuals with ERCC2 Mutations or TTD-Affected Individuals with GTF2E2 Mutations

	TTD (ERCC2) Features	TTD379BE (GTF2E2) (c.448G>C [p.Ala150Pro])	TTD28PV (GTF2E2) (c.559G>T [p.Asp187Tyr])	XP (ERCC2) Features	Normal
repair + TRANSCRIPTION defecta	TRANSCRIPTION defect	TRANSCRIPTION defect	REPAIR + transcription defect	normal
DNA Repair
Reduced post-UV cell survival and host cell reactivation	yes	no	no	yes	no
Reduced repair of cyclobutane pyrimidine dimer photoproducts	yes	no	no	yes	no
Reduced XPB and XPD proteins	yes	no	no	yes	no
Transcription
Reduced TFIIEβ protein	no	yes	yes	no	no
Reduced TFIIEα protein	no	yes	yes	no	no
Reduced phosphorylated TFIIEα protein in confluent cells	yes	yes	yes	no	no

^aTerms in all capital letters indicate greater contribution to the phenotype.