# Cas9 activity scores

**URL:** <https://forum.depmap.org/t/cas9-activity-scores/847>\
**Category:** Resolved Issues\
**Tags:** genetic-screens\
**Created:** [August 23, 2021, 7:08pm UTC](https://forum.depmap.org/t/cas9-activity-scores/847 "2021-08-23T19:08:52Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![rkarnik](https://yyz1.discourse-cdn.com/flex035/user_avatar/forum.depmap.org/rkarnik/32/302_2.png) [@rkarnik](https://forum.depmap.org/u/rkarnik)\
**Post date:** [August 23, 2021, 7:08pm UTC](https://forum.depmap.org/t/cas9-activity-scores/847/1 "2021-08-23T19:08:52Z")

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In the sample\_info.csv file, I see a cas9\_activity column. The description says it is the percentage of **GFP-positive** cells, which is the reverse of cas9\_activity, if I correctly understand the assay being used. Is that true? The scores range from 23 to 99+, which suggests that the best cell lines only show edits in about 80% of cells, and several lines are lower than that.

Is this actually reversed, and the cas9\_activity number is the percentage of **GFP-negative** cells?

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**Author:** ![Joshua\_Dempster](https://yyz1.discourse-cdn.com/flex035/user_avatar/forum.depmap.org/joshua_dempster/32/19_2.png) [@Joshua\_Dempster](https://forum.depmap.org/u/Joshua_Dempster)\
**Post date:** [August 24, 2021, 4:46pm UTC](https://forum.depmap.org/t/cas9-activity-scores/847/2 "2021-08-24T16:46:26Z")

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The README is out of date. The cas9\_activity column being reported now is the percent negative GFP cells, so that a higher number indicates greater cas9 efficacy. We’ll fix this for future releases.

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**Author:** ![rkarnik](https://yyz1.discourse-cdn.com/flex035/user_avatar/forum.depmap.org/rkarnik/32/302_2.png) [@rkarnik](https://forum.depmap.org/u/rkarnik)\
**Post date:** [August 24, 2021, 5:49pm UTC](https://forum.depmap.org/t/cas9-activity-scores/847/3 "2021-08-24T17:49:28Z")

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Good to know. Thanks Joshua!