Previous symbols: VDD1, PDDR. Aliases: CYP1, P450c1.
CYP27B1 (cytochrome P450 family 27 subfamily B member 1) is named by 1 disorder entry.
CYP27B1 is the mitochondrial 25-hydroxyvitamin D 1-alpha-hydroxylase that makes calcitriol, the rate-limiting step of vitamin D activation. The ai-gene-review gene review for CYP27B1 is new and is not yet in the pinned ingest snapshot, so the ingest layer currently lists 0 core-function terms for it.
The one entry types CYP27B1 as causative: Vitamin D-Dependent Rickets Type 1A, with germline variants (germline). The gene sits on the node Renal 1-Alpha-Hydroxylase Deficiency. ClinGen rates CYP27B1 definitive for this disease.
ClinGen classifies CYP27B1 for 1 disease, and no matched dismech entry leaves the gene untyped (0).
Underlined values are claims re-computed from the knowledge base each time this page is built. The tables below are the source of truth.
Relationship is the entry's genetic[].relationship_type. untyped means the entry has a genetic record for the gene but does not type it; its free-text association is shown instead.
| Disorder | Relationship | Where the gene appears |
|---|---|---|
| Vitamin D-Dependent Rickets Type 1A |
causative
germline
CLINGEN: definitive
|
mechanism: Renal 1-Alpha-Hydroxylase Deficiency
|
An entry matches when ClinGen's MONDO disease is the entry's own disease term, a subtype term, or an exact-match mapping. An amber status marks an entry ClinGen supports the gene for (Definitive, Strong or Moderate) whose own record does not type it. A Limited, Disputed or Refuted tier on such an entry is not a gap.
| ClinGen disease | MOI | Classification | dismech entry |
|---|---|---|---|
| vitamin D-dependent rickets, type 1A MONDO:0020723 | AR | Definitive 2025-06-04 |
Vitamin D-Dependent Rickets Type 1A
causative
|
Identity from HGNC (snapshot 2026-10-01). Page layers are described in the gene pages documentation.