| Diagnosis | Omim Number | Sample Count |
| PALLIDOPONTONIGRAL DEGENERATION | | 3 |
| PANTOTHENATE KINASE-ASSOCIATED NEURODEGENERATION; PKAN; HALLERVORDEN-SPATZ DISEASE INCLUDED | 234200 | 1 |
| PAPULAR MUCINOSIS; GENETIC OR ACQUIRED | | 3 |
| PARANA HARD-SKIN SYNDROME | 260530 | 1 |
| PARKIN; PARK2 | 602544 | 1 |
| PARKINSON DISEASE | 168600 | 4495 |
| PARKINSON DISEASE,FAMILIAL, TYPE 1; PARK1 | 168601 | 6 |
| PARKINSONISM, OTHER | | 15 |
| PAROXYSMAL EXERCISE INDUCED DYSTONIA | | 1 |
| PAROXYSMAL EXTREME PAIN DISORDER; PEPD | 167400 | 1 |
| PEARSON MARROW-PANCREAS SYNDROME | 557000 | 4 |
| PELIZAEUS-MERZBACHER DISEASE; PMD | 312080 | 25 |
| PEROXISOMAL BIFUNCTIONAL ENZYME DEFICIENCY | 261515 | 4 |
| PEROXISOME BIOGENESIS DISORDER 3A (ZELLWEGER); PBD3A | | 1 |
| PEROXISOME BIOGENESIS DISORDER 4A (ZELLWEGER); PBD4A | | 4 |
| PEROXISOME BIOGENESIS DISORDER 7A (ZELLWEGER); PBD7A | | 3 |
| PEROXISOME BIOGENESIS DISORDER 7B; PBD7B | | 1 |
| PEROXISOME BIOGENESIS DISORDER 8A (ZELLWEGER); PBD8A | | 1 |
| PETERS-PLUS SYNDROME | 261540 | 1 |
| PFEIFFER SYNDROME | 101600 | 1 |
| PHENYLKETONURIA | 261600 | 14 |
| PHOSPHOGLYCERATE KINASE 1 DEFICIENCY | | 4 |
| PICK DISEASE OF BRAIN | 172700 | 1 |
| PIEBALD TRAIT; PBT | 172800 | 1 |
| PITT-HOPKINS SYNDROME; PTHS | | 34 |
| POLYCYSTIC KIDNEY AND HEPATIC DISEASE 1; PKHD1 | 263200 | 1 |
| POLYCYSTIC KIDNEY AND HEPATIC DISEASE 1; PKHD1 | 263200 | 3 |
| POLYCYSTIC KIDNEYS | 173900 | 7 |
| POLYDACTYLY WITH NEONATAL CHONDRODYSTROPHY, TYPE II, MAJEWSKI TYPE | 263520 | 2 |
| POPLITEAL PTERYGIUM SYNDROME, LETHAL TYPE; BARTSOCAS-PAPAS SYNDROME; BPS | 263650 | 1 |
| PORPHYRIA - COPROPORPHYRIA | 121300 | 2 |
| PORPHYRIA CUTANEA TARDA | 176100 | 11 |
| PORPHYRIA VARIEGATA | 176200 | 1 |
| PORPHYRIA, ACUTE HEPATIC | | 2 |
| PORPHYRIA, ACUTE INTERMITTENT | 176000 | 22 |
| PORPHYRIA, CONGENITAL ERYTHROPOIETIC | 263700 | 4 |
| PRADER-WILLI SYNDROME; PWS | 176270 | 61 |
| PRIMARY ANGLE-CLOSURE GLAUCOMA | | 1 |
| PRIMARY LATERAL SCLEROSIS | | 126 |
| PROGERIA, ADULT ONSET | | 3 |
| PROGEROID SYNDROME, NEONATAL | 264090 | 3 |
| PROGRESSIVE BULBAR PALSY | | 11 |
| PROGRESSIVE MUSCULAR ATROPHY | | 101 |
| PROGRESSIVE SUPRANUCLEAR PALSY | 601104 | 375 |
| PROPIONIC ACIDEMIA | 606054 | 52 |
| PROSTATE CANCER | 176807 | 3 |
| PROTEUS SYNDROME | 176920 | 5 |
| PROTHROMBIN DEFICIENCY, CONGENITAL | | 1 |
| PROTOPORPHYRIA, ERYTHROPOIETIC | 177000 | 4 |
| PRUNE BELLY SYNDROME; PBS | 100100 | 1 |
| PSEUDOACHONDROPLASTIC DYSPLASIA | 177170 | 1 |
| PSEUDOHERMAPHRODITISM, MALE, WITH GYNECOMASTIA | 264300 | 1 |
| PSEUDOHYPOPARATHYROIDISM, TYPE IA; PHP1A | 103580 | 5 |
| PSEUDONEONATAL ADRENOLEUKODYSTROPHY | 264470 | 6 |
| PSEUDOTRISOMY 13 SYNDROME (HOLOPROSENCEPHALY-POLYDACTYLY SYNDROME) | 264480 | 1 |
| PSEUDOVAGINAL PERINEOSCROTAL HYPOSPADIAS; PPSH | 264600 | 1 |
| PSEUDOXANTHOMA ELASTICUM, AUTOSOMAL RECESSIVE; PXE | 264800 | 1 |
| PTERYGIUM OF CONJUNCTIVA AND CORNEA | 178000 | 2 |
| PYROGLUTAMICACIDURIA | 266130 | 2 |
| PYRUVATE CARBOXYLASE DEFICIENCY | 266150 | 2 |
| PYRUVATE DECARBOXYLASE DEFICIENCY | 312170 | 2 |