Xenobiotic Sensor- and Metabolism-Related Gene Variants in Environmental Sensitivity-Related Illnesses: A Survey on the Italian Population

Table 1

Allele and genotype frequencies of some drug metabolism-related gene variants in SRI patients (MCS: multiple chemical sensitivity; sMCS: suspected multiple chemical sensitivity; FM/CFS: fibromyalgia/chronic fatigue syndrome) and healthy subjects (Ctr: controls).

Genotype	MCS	SMCS	FM/CFS	Ctr
CYP2C9	𝑁 = 101	𝑁 = 94	𝑁 = 80	𝑁 = 90
Wt	66.3%	66%	55%	84.4%
Ht*1/*2	23.8%^†	18.1%	15%	12.2%
Ht*1/*3	6.9%†,§§	11.7%^††	20%^††††	1.1%
PM*2/*2	0.9%	2.1%	3.75%	2.2%
PM*2/*3	0.9%	—	2.5%	—
PM*3/*3	0.9%	2.1%	3.75%	—
* 2 allele frequency	0.132^§§	0.111^§	0.125^†	0.083
* 3 allele frequency	0.048^††	0.079^†††	0.15^††††	0.007
CYP2C19	𝑁 = 101	𝑁 = 93	𝑁 = 80	𝑁 = 62
Wt	61.4%	84.8%	78.8%	80.3%
Ht*1/*2	36.6%^††,###,§	14.1%	20.0%	16.7%
PM*2/*2	2.0%	1.1%	1.3%	3.0%
* 2 allele frequency	0.203^†,§,##	0.081	0.113	0.113
CYP2D6	𝑁 = 55	𝑁 = 93	𝑁 = 75	𝑁 = 113
Wt	40%	52.7%	40.7%	77.9%
Ht*1/*4	36.4%^††	25.8%^†	28.5%^†	18.6%
Ht*1/*41	14.8%^††††	5.4%^††††	7.4%^††††	—
PM*4/*4	5.5%	4.3%	8.5%	3.5%
PM*4/*41	3.6%	7.5%	7.4%	—
PM*41/*41	—	4.3%	7.4%	—
* 4 allele frequency	0.255^†††	0.209^††	0.314^††††	0.128
* 41 allele frequency	0.092^††††	0.107^††††	0.148^††††	—

^†𝑃 < 0.05 versus Ctr, ^††𝑃 < 0.01 versus Ctr; ^†††𝑃 < 0.001 versus Ctr, ^††††𝑃 < 0.0001 versus Ctr;   ^§𝑃 < 0.05 versus FM/CFS;   ^§§𝑃 < 0.01 versus FM/CFS; ^#𝑃 < 0.05 versus SMCS; ^##𝑃 < 0.01 versus SMCS; ^###𝑃 < 0.001 versus SMCS.