Table 2.

Genotype distribution of GSTM1 and GSTT1 alleles in both healthy controls and tannery workers.

Study subjects	GSTM1/GSTT1	GSTM1/GSTT1	GSTM1/GSTT1	GSTM1/GSTT1
	(+/+), %	(+/−), %	(−/+), %	(−/−), %
Total	50.0	12.2	31.4	6.4
n = 188	n = 94	n = 23	n = 59	n = 12
Healthy controls	54.1	9.2	32.1	4.6
n = 109	n = 59	n = 10	n = 35	n = 5
Tannery workers	44.3	16.8	30.5	8.4
n = 79	n = 35	n = 13	n = 24	n = 7

n = number of individuals. +/+ indicates presence of both GSTM1 and GSTT1 alleles; +/− indicates presence of GSTM1 and absence of GSTT1 alleles (GSTT1 null genotypes); −/+ indicates absence of GSTM1 and presence of GSTT1 alleles (GSTM1 null genotypes); −/− indicates absence of both GSTM1 and GSTT1 alleles.