| Diagnosis | Omim Number | Sample Count |
| UBA5-RELATED DISORDER | | 6 |
| ULLRICH CONGENITAL MUSCULAR DYSTROPHY; UCMD1 | 254090 | 38 |
| UNIPARENTAL DISOMY CHROMOSOME 2 | | 1 |
| UNIPARENTAL DISOMY CHROMOSOME 8 | | 1 |
| USHER SYNDROME, TYPE IA; USH1A | 276900 | 6 |
| USHER SYNDROME, TYPE IA; USH1A | 276900 | 45 |
| USHER SYNDROME, TYPE IC; USH1C | 276904 | 29 |
| USHER SYNDROME, TYPE IIA; USH2A | 276901 | 9 |
| USHER SYNDROME, TYPE IIC; USH2C | | 3 |