Table 1.

ATM-deficiency causes early embryonic lethality in mice deficient in the components of the DNA-PK holoenzyme

Age	Genotype	ATM+/+	ATM+/−	ATM−/−
Live-born pups	Ku70−/−	16 (10)	12 (20)	0 (10)
	Ku80−/−	13 (13)	24 (25)	0 (13)
	scid	21 (16)	44 (33)	0 (16)
E13–16	Lig4−/−	9 (10)	18 (20)	16 (10)
E11.5–13.5	Ku80−/−	8 (11)	23 (22)	0 (11)

The number of live-born pups and embryos at the indicated developmental stages of the relevant genotypes (as indicated) is shown with the expected Mendelian numbers in parentheses. No scid^−/− ATM^−/− pups were observed in over 360 pups born from scid^+/− ATM^+/− intercrosses (data not shown). In preliminary results, no live-born DNA-PKcs^−/− ATM^−/− pups were observed in breedings between DNA-PKcs^+/− ATM^+/− mice, and no scid^−/− ATM^−/− embryos (E12) from breedings between scid^−/− ATM^+/− and scid^+/− ATM^+/− mice were observed.