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System issues: A test for neutrality of mutations of the lacZ transgene

✍ Scribed by Lidia Cosentino; John A. Heddle

Publisher: John Wiley and Sons
Year: 1996
Tongue: English
Weight: 353 KB
Volume: 28
Category: Article
ISSN: 0893-6692
DOI: 10.1002/(sici)1098-2280(1996)28:4<313::aid-em3>3.0.co;2-c

No coin nor oath required. For personal study only.

✦ Synopsis

Neutral mutations are stable alterations in DNA that are neither beneficial nor damaging to the cell. Once a mutation is fixed in the DNA, the mutant frequency should increase to its maximum and plateau thereafter, provided that enough expression time is given. Evidence has been obtained indicating neutrality for the endogenous Dlb-I locus and for the lac/ in the BigBluem transgenic system, and is reported here for IacZ in the MutamMouse system. W e have found that, after an acute dose of ethylnitrosourea (ENU, 250 mg/kg) the mutant frequency for both lacZ transgene and Dlb-I remained constant between 10 and 70 days after mutagenesis in the small intestine, where cell turnover is rapid (-7 days). The same concept should apply to other tissues.

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