TABLE 3

Allelic frequency and prevalence of UGT1A7 alleles


UGT1A7 Alleles

Functiona

Frequency (%)b
UGT1A7*1c High 32.2
UGT1A7*2 K129/K131 High 30.6
UGT1A7*3 K129/K131/R208 Low 31.6
UGT1A7*4 R208 Low 2.5
UGT1A7*5 S115 Low 0.5
UGT1A7*6 D139 High 0.2
UGT1A7*7 K129/K131/D139 High 2.1
UGT1A7*8 K129/K131/D139/R208 Low 0.2
UGT1A7*9
S115/K129/K131
Low
0.3
UGT1A7 Genotypesd
Population (n = 317)e
Frequency (%)
*1/*1 30 9.5
*1/*2 57 18.0
*1/*3 or *2/*4 72 22.7
*1/*4 6 1.9
*1/*6 1 0.3
*1/*7 *2/*6 7 2.2
*1/*8, *3/*6 or *4/*7 1 0.3
*2/*2 39 12.3
*2/*3 55 17.4
*2/*7 3 1.0
*2/*8 or *3/*7 1 0.3
*2/*9 1 0.3
*3/*3 35 11.0
*3/*7 2 0.6
*4/*4 5 1.6
*5/*5 1 0.3
*5/*9 1 0.3
Low activityf 42 13.3
Intermediate activityg
138
43.5
  • a Activities based on in vitro experiments normalized by the expressed UGT protein levels: low, significantly lower SN-38G formation versus *1 allele; high, no significant difference in activity compared with *1 allele.

  • b Population of 167 Caucasian and 150 African-American subjects.

  • c UGT1A7*1: G115/N129/R131/E139/W208; only position differing from *1 are indicated.

  • d In bold: Genotypes considered to evaluate allelic frequencies;

  • e 167/317 Caucasian; 150/317 African-American subjects.

  • f With two low activity alleles.

  • g With one low activity allele.