Table 2.

Genotype and allele frequencies of the C/T polymorphism in MDR gene

	COPD		Control
	n	%	n	%
Genotype Frequency
MDR C/T polymorphism
CC	8	17.0	25	39.1
CT	24	51.1	34	53.1
TT	15	31.9	5	7.8
Total	47		64
X2 = 13.554; df = 2; P = 0.001
Allele Frequency
MDR C allele	40	32.3	84	67.7
MDR T allele	54	55.1	44	44.9
X2 = 10.784; df = 1; P = 0.001