CYP2R1 notes

Deep research (just deep-research-falcon human CYP2R1) was attempted on 2026-10-10 and failed (all providers
failed / timeout). Literature work was done manually from the cached GOA publications plus PubMed.

• Microsomal vitamin D 25-hydroxylase identified by expression cloning PMID:12867411.
• Kinetics vs CYP27A1 PMID:15465040.
• Crystal structure with vitamin D3; narrow substrate specificity PMID:18511070.
• Human genetics: L99P homozygote with low 25(OH)D (VDDR1B) PMID:15128933; Nigerian families, semidominant PMID:27473561.
• Cyp2r1-null mice: >50% lower serum 25(OH)D3; a second unknown 25-hydroxylase exists PMID:24019477.
• Review decisions: xenobiotic metabolic process IBA removed (narrow secosteroid specificity); cytoplasm IBA modified to ER membrane.
• Disease: dismech Vitamin_D-Dependent_Rickets_Type_1B binds GO:0030343 (LOSS_OF_FUNCTION) — consistent with core function.