COVID-19 is an emerging, rapidly evolving situation.

Get the latest public health information from CDC and research information from NIH.

U.S. flag

An official website of the United States government

Dot gov

The .gov means it's official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you're on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Share This:
Study Information
Study Attribute Value
CEBS Accession Number: 002-01560-0001-0000-5
Chemical Name: 6-Thioguanine (6-TG)
CASRN: 154-42-7
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: A59828_CA
Study Result: Positive

Study Result: Positive
Activation Trial Trial Call
No Activation  1  Positive 
Induced Rat Liver S9  1_S9  Positive 
No Activation  2  Positive 

Trial #:1   Activation: No Activation    Date: 06/07/1995    Harvest Time: 12 hour(s)   Trial Call: Positive   
  Dose
µg/mL		 Total
Cells Examined		 Total Aberrations Complex Aberrations Simple Aberrations Other Abs
No. of
Abs		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs
Vehicle Control: Dimethyl Sulfoxide 
0         
 200 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Negative (Not Specified) 
0         
 200 2 0.010 1.0 1 0.005 0.5 1 0.005 0.5 0 0.000 0.0
Test Chemical: 6-Thioguanine (6-TG) 
6.25      
 200 10 0.050 4.5 3 0.015 1.5 7 0.035 3.0 0 0.000 0.0 
12.5       
 200 55 0.275 21.0 5 0.025 2.5 49 0.245 19.0 1 0.005 1.0 
25         
 200 77 0.385 25.0 5 0.025 2.5 72 0.360 22.5 0 0.000 0.0 
50         
 50 87 1.740 68.0 2 0.040 4.0 85 1.700 66.0 0 0.000 0.0
Positive Control: Mitomycin-C 
 0.0625    
 200 33 0.165 13.0 7 0.035 3.5 26 0.130 9.5 0 0.000 0.0
Mitomycin-C 
 0.25      
 50 30 0.600 38.0 13 0.260 24.0 17 0.340 22.0 0 0.000 0.0
Trend: 11.913 2.384 11.739  
Probability: 0.000 0.009 0.000  


Trial #:1_S9   Activation: Induced Rat Liver S9    Date: 06/07/1995    Harvest Time: 13 hour(s)   Trial Call: Positive   
  Dose
µg/mL		 Total
Cells Examined		 Total Aberrations Complex Aberrations Simple Aberrations Other Abs
No. of
Abs		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs
Vehicle Control: Dimethyl Sulfoxide 
0         
 200 2 0.010 1.0 0 0.000 0.0 2 0.010 1.0 0 0.000 0.0
Test Chemical: 6-Thioguanine (6-TG) 
200         
 200 19 0.095 7.0 1 0.005 0.5 18 0.090 6.5 0 0.000 0.0 
300         
 200 42 0.210 17.0 3 0.015 1.5 39 0.195 16.0 0 0.000 0.0 
400         
 200 33 0.165 12.5 3 0.015 1.5 30 0.150 12.0 0 0.000 0.0 
500         
 200 45 0.225 16.5 1 0.005 0.5 44 0.220 16.5 0 0.000 0.0
Positive Control: Cyclophosphamide 
2.5       
 200 28 0.140 13.5 6 0.030 3.0 22 0.110 11.0 0 0.000 0.0
Cyclophosphamide 
7.5       
 50 27 0.540 42.0 8 0.160 16.0 18 0.360 28.0 1 0.020 1.0
Trend: 5.444 1.176 5.504  
Probability: 0.000 0.120 0.000  


Trial #:2   Activation: No Activation    Date: 06/19/1995    Harvest Time: 12 hour(s)   Trial Call: Positive   
  Dose
µg/mL		 Total
Cells Examined		 Total Aberrations Complex Aberrations Simple Aberrations Other Abs
No. of
Abs		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs
Vehicle Control: Dimethyl Sulfoxide 
0         
 200 2 0.010 1.0 1 0.005 0.5 1 0.005 0.5 0 0.000 0.0
Test Chemical: 6-Thioguanine (6-TG) 
12.5       
 200 40 0.200 13.5 1 0.005 0.5 39 0.195 13.0 0 0.000 0.0 
25         
 200 61 0.305 23.5 5 0.025 2.0 56 0.280 22.0 0 0.000 0.0 
37.5       
 200 121 0.605 35.5 6 0.030 3.0 115 0.575 33.5 0 0.000 0.0 
50         
 200 147 0.735 37.0 10 0.050 4.5 137 0.685 33.5 0 0.000 0.0
Positive Control: Mitomycin-C 
 0.0625    
 200 41 0.205 17.0 17 0.085 8.0 24 0.120 11.5 0 0.000 0.0
Mitomycin-C 
 0.25      
 50 20 0.400 38.0 8 0.160 16.0 12 0.240 22.0 0 0.000 0.0
Trend: 10.255 3.210 9.737  
Probability: 0.000 0.001 0.000