I recommend to accept this paper as is for the following two major reasons: It is interisting in the field of inborn errors of immunity, yet also interesting for a broader readership in the advent/ era of pharmaceutical Factor D inhibition.

The auhthors provide molecular genetic information that is functionally validated. Factor D deficiency was restored ex vivo and so proven beyond any doubt.

Detailed reasons for my suggestion to accept as is:
1) PAtients with Factor D deficiency are still exceedingly rarely reported. So every publication fruther contributes to the description of the clincal phenotype.
2) Along this line: It is important to report that there was an invasive infection by Hämophilus Type b in one of the two patients, as this has been rarely reported before.
3) Patient with Down Syndrome must be investigated for inborn errors of immunity as if there were no Down Syndrome!
4) In the advent of pharmacuetical Factor D inhibition such reports are important also for a braoder readership, beyond the clinicians caring for inborn errors of immunity