Table 2.
UGT1A1 allele naming conventions, locations, and associated phenotypes
| UGT1A1 allelea | Variant | Location | Enzyme activity | Associated phenotype |
|---|---|---|---|---|
| UGT1A1*1 | (TA)6TAA | Promoter | Normal | Wild type |
| UGT1A1*28 | (TA)7TAA | Promoter | Reduced | Gilbert syndrome |
| UGT1A1*36 | (TA)5TAA | Promoter | Increased | |
| UGT1A1*37 | (TA)8TAA | Promoter | Reduced | Crigler-Najjar, type II |
| UGT1A1*6 | c.211G>A; G71R | Exon 1 | Reduced | Gilbert syndrome |
| UGT1A1*27 | g.686C>A; P229Q | Exon 1 | Reduced | Gilbert syndrome |
a
Allele frequencies, stratified by race, are shown in Table 4.