# Transmission Disequilibrium Test help **URL:** \ **Category:** Hail Query & hailctl\ **Created:** [July 5, 2023, 11:00pm UTC](https://discuss.hail.is/t/transmission-disequilibrium-test-help/3467 "2023-07-05T23:00:32Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![MsUTR](https://avatars.discourse-cdn.com/v4/letter/m/a9adbd/32.png) [@MsUTR](https://discuss.hail.is/u/MsUTR)\ **Post date:** [July 5, 2023, 11:00pm UTC](https://discuss.hail.is/t/transmission-disequilibrium-test-help/3467/1 "2023-07-05T23:00:32Z")
Dear all, I am trying to use the `hl.transmission_disequilibrium_test()` function to extract transmitted and untransmitted variants. As a part of the QC, I am planning to apply some entry-level filters: ```python mt = mt.filter_entries(mt.AD[1] >= 3) mt = mt.filter_entries(mt.DP >= 10) mt = mt.filter_entries(mt.DP < 1000) mt = mt.filter_entries(mt.GQ >= 20) ``` Unfortunately, if I do this, my entire `tdt` Hail table is NA for all `t` and `u` fields: ```python |locus|alleles|t|u|chi_sq|p_value| |locus|array|int64|int64|float64|float64| |1:861266|["G","C"]|NA|NA|NA|NA| |1:861303|["G","C"]|NA|NA|NA|NA| |1:865579|["C","T"]|NA|NA|NA|NA| ``` When I do not do entry-level filtering, the `t` and `u` have integer values. May I ask if there is any advice to incorporate entry-level filtering with `hl.transmission_disequilibrium_test()`? Thank you! ---
**Author:** ![danking](https://yyz2.discourse-cdn.com/flex036/user_avatar/discuss.hail.is/danking/32/43_2.png) [@danking](https://discuss.hail.is/u/danking)\ **Post date:** [July 10, 2023, 8:47pm UTC](https://discuss.hail.is/t/transmission-disequilibrium-test-help/3467/2 "2023-07-10T20:47:29Z")
As currently implemented, the test doesn’t support missing or filtered entry values. The [implementation](https://github.com/hail-is/hail/blob/main/hail/python/hail/methods/family_methods.py#L342-L512) is rather short but I’m not a geneticist and don’t know how to modify it appropriately to handle missing data. You might try your hand at modifying it yourself.