The homozygous deletion of the Dhps gene results in embryonic lethality (Nishimura et al. 2012) and biallelic variants in the DHPS gene in humans have been linked to a neurodevelopmental disorder (Ganapathi et al. 2019), evidencing that DHPS activity is globally essential for embryogenesis and homeostasis, and therefore constitutively expressed. The gene discussed is DHPS; the disease is neurodevelopmental disorder.