| Db | Link | Name | Definition | Comment | Is a |
|---|---|---|---|---|---|
| OMIM | OMIM:123150 | JACKSON-WEISS SYNDROME; JWS | — | — | — |
| OMIM | OMIM:123155 | HYDROCEPHALUS, AUTOSOMAL DOMINANT; HDCPH1 | — | — | — |
| OMIM | OMIM:123270 | CREATINE KINASE, BRAIN TYPE, ECTOPIC EXPRESSION OF; CKBE | — | — | — |
| OMIM | OMIM:123320 | CREATINE PHOSPHOKINASE, ELEVATED SERUM | — | — | — |
| OMIM | OMIM:123400 | CREUTZFELDT-JAKOB DISEASE; CJD | — | — | — |
| OMIM | OMIM:123450 | CRI-DU-CHAT SYNDROME | — | — | — |
| OMIM | OMIM:123500 | CROUZON SYNDROME | — | — | — |
| OMIM | OMIM:123540 | CRYOFIBRINOGENEMIA, FAMILIAL PRIMARY | — | — | — |
| OMIM | OMIM:123550 | CRYOGLOBULINEMIA, FAMILIAL MIXED | — | — | — |
| OMIM | OMIM:123555 | MOVED TO 125220 | — | — | — |
| OMIM | OMIM:123557 | CRYPTOTIA, FAMILIAL | — | — | — |
| OMIM | OMIM:123560 | CRYPTOMICROTIA-BRACHYDACTYLY SYNDROME | — | — | — |
| OMIM | OMIM:123570 | CRYPTOPHTHALMOS, UNILATERAL OR BILATERAL, ISOLATED | — | — | — |
| OMIM | OMIM:123700 | CUTIS LAXA, AUTOSOMAL DOMINANT 1; ADCL1 | — | — | — |
| OMIM | OMIM:123710 | MOVED TO 123660 | — | — | — |
| OMIM | OMIM:123720 | MOVED TO 123660 | — | — | — |
| OMIM | OMIM:123790 | BEARE-STEVENSON CUTIS GYRATA SYNDROME; BSTVS | — | — | — |
| OMIM | OMIM:123839 | MOVED TO 600262 | — | — | — |
| OMIM | OMIM:123850 | MOVED TO 132700 | — | — | — |
| OMIM | OMIM:123853 | CYPRUS FACIAL NEUROMUSCULOSKELETAL SYNDROME | — | — | — |
| OMIM | OMIM:123880 | CYSTIC ANGIOMATOSIS OF BONE, DIFFUSE | — | — | — |
| OMIM | OMIM:123950 | MOVED TO 250790 | — | — | — |
| OMIM | OMIM:123960 | MOVED TO 122720 | — | — | — |
| OMIM | OMIM:123997 | CYTOCHROME c OXIDASE, SUBUNIT 7A2, PSEUDOGENE 2; COX7A2P2 | — | — | — |
| OMIM | OMIM:124000 | MITOCHONDRIAL COMPLEX III DEFICIENCY, NUCLEAR TYPE 1; MC3DN1 | — | — | — |