# Can the Gnomad PCA Be Used for Exomes?

**URL:** <https://discuss.hail.is/t/can-the-gnomad-pca-be-used-for-exomes/3695>\
**Category:** Hail Query & hailctl\
**Created:** [December 29, 2023, 3:50pm UTC](https://discuss.hail.is/t/can-the-gnomad-pca-be-used-for-exomes/3695 "2023-12-29T15:50:12Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![beneopp](https://yyz2.discourse-cdn.com/flex036/user_avatar/discuss.hail.is/beneopp/32/1083_2.png) [@beneopp](https://discuss.hail.is/u/beneopp)\
**Post date:** [December 29, 2023, 3:50pm UTC](https://discuss.hail.is/t/can-the-gnomad-pca-be-used-for-exomes/3695/1 "2023-12-29T15:50:12Z")

</div>

I have exome vcf data and would like to use the PCA from gnomad to determine the ancestries of my samples?

The following [blog](https://gnomad.broadinstitute.org/news/2021-09-using-the-gnomad-ancestry-principal-components-analysis-loadings-and-random-forest-classifier-on-your-dataset/) discussing PCA says:

```python
If your dataset is missing large numbers of the variants with gnomAD PCA loadings, it will produce unreliable results. 

```

Does that mean exome data cannot be used? Will also ask this question on the gnomAD forum in case it is something they would know.

Thank you

---

<div class="post-metadata">

**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:** [January 2, 2024, 2:31pm UTC](https://discuss.hail.is/t/can-the-gnomad-pca-be-used-for-exomes/3695/2 "2024-01-02T14:31:00Z")

</div>

Hey @beneopp ! We (Hail team) lack the expertise to answer this question. Could you repost this at the gnomAD forum? [https://discuss.gnomad.broadinstitute.org](https://discuss.gnomad.broadinstitute.org)