Table 10Gender related differences in TPMT enzymatic activity

StudyMaleFemaleSignificance
Hindorf
2004111
12.9 (range, 0.2–24.6) U/mL RBCs
(n=607)
12.7 (range, 0.4–25.4) U/mL RBCs
(n=544)
p = 0.08
Weinshilboum
1978134
10.0 ± 2.3 U/mL RBCs
(n = 37)
10.4 ± 2.5 U/mL RBCs
(n = 36)
Tinel
1991131
14.6 ± 6.7 U/mL RBCs
(n=119)
16.8 ± 7.7 U/mL RBCs
(n=184)
Jacqz-Aigrain
1994128
19.6 ± 4.9 U/mL RBC
(n=134)
18.9± 4.9 U/mL RBC
(n=166)
Kroplin
1998124
38.8 nmol 6-MTG/h/g Hb
(n=117)
36.9 nmol 6-MTG/h/g Hb
(n=82)
Keizer- Garritsen
2003116
15,8± 6,4 pmol/h/107 RBCs
(n=59)
15,1± 4,8 pmol/h/107 RBCs
(n=44)
Ganiere- Monteil
2004113
Adults: 19.55± 4.25 U/mL RBCs
(n= 229)
Children: 18.34±4.21 U/mL RBCs
(n=97)
Adults: 18.61±3.59 U/mL RBCs.
(n=75)
Children: 18.87±3.98 U/mL RBCs
(n=50)
Adults: p=0.057.
Children: p=0.310
Ford
2004112
Mean and median TPMT activities: 34 and 34 nmol 6- MTG/h/g Hb (n=469)Mean and median TPMT activities: 33 and 32 nmol 6- MTG/h/g Hb
(n=531)
No significant difference
Zhang
2007106
Wild type Healthy: (n=155)
17.05±3.12 U/ml RBCs
Heterozygous Healthy:
(n=4)7.50±1.58 U/ml RBCs
Wild type Healthy: (n=86)
15.90±2.87 U/ml RBCs.
Heterozygous Healthy: (n=3)
8.17±1.30 U/ml RBCs
p=0.01
Zhang
2006135
12,36 U/mL RBCs
(n=5)
13,16 U/mL RBCs
(n=14)
Chocair
1993129
Caucasians: (n = 21)
38 U/g Hb
Black: (n = 24)
38 U/g Hb
Mixed-race: (n = 19)
39 U/g Hb
Japanese: (n = 11)
37 U/g Hb
Caucasians: (n = 12)
30 U/g Hb
Black: (n = 15)
36.5 U/g Hb
Mixed-race: (n = 11)
33 U/g Hb
Japanese: (n = 21)
38 U/g Hb
Micheli
1997125
Adults (20–59 y): (n=7)
21 ± 5 U/g Hb
Children (1–14y): (n = 6)
23 ± 5.8 U/g Hb
Adults (20–59 y): (n=7)
15± 8 U/g Hb
Children (1–14y): (n = 2)
18.21 U/g Hb
Menor
2002117
19.7 - 6.2 U/mL RBCs
(n=1671)
19.5 - 6.1 U/mL RBCs
(n=1873)
Brouwer
2005110
ALL patients: Median TPMT: 12.4 (range 1.7–30.7) pmol/hr/107 RBCs (n=116)ALL patients: Median TPMT: 12.8 (range 5.8–30.4) pmol/hr/107 RBCs (n=57)No significant difference for ALL patients (p = 0.841)
Oselin
2006107
n=52n=47No significant difference
TPMT activity:
21.5 to 129.6 ng/h/mL RBCs
Lennard
1994127
In children, boys versus girls TPMT activity for the entire group (n=100) not significantly different (p > 0.25, Mann-Whitney).
High TPMT activity group (n=100) boys versus girls not significantly different (p=0.8)
Alves
2001122
(n=76)(n=67)No statistically significant association (p = 0.796, ANOVA).
Lee
1982133
Renal cell carcinoma patients
232 ± 9 U/g tissue or 4.24 ± 0.15 U/mg protein
(n=37 )
Renal cell carcinoma patients
210 ± 21 U/g of tissue or 3.93 ± 0.4 U/mg of protein
(n=14)
No significant differences. Imbalance in sample numbers likely due to the 2:1 male:female incidence of renal cell carcinoma.

Abbreviations: 6-MTG = 6-methylthioguanine ALL = acute lymphoblastic leukemia; ANOVA = analysis of covariance; g = gram; mL RBCs = milliliter of red blood cells; p = probability; pmol = picomole; TPMT = thiopurine methyltransferase; U = Unit = nanomole of product per hour

From: 3, Results

Cover of Assessment of Thiopurine Methyltransferase Activity in Patients Prescribed Azathioprine or Other Thiopurine-Based Drugs
Assessment of Thiopurine Methyltransferase Activity in Patients Prescribed Azathioprine or Other Thiopurine-Based Drugs.
Evidence Reports/Technology Assessments, No. 196.
Booth RA, Ansari MT, Tricco AC, et al.

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