Table 1. Degrees of ITPA deficiency according to rs1127354/rs7270101 genotypes combinations (0–3: no ITPA deficiency, mild, moderate or severe deficiency).

rs1127354	rs7270101	Predicted ITPA activity	Predicted ITPA deficiency
Wild-type (C/C)	Wild-type (A/A)	100%	0
Wild-type (C/C)	Heterozygosity (A/C)	60%	1
Heterozygosity (C/A)	Wild-type (A/A)	30%	2
Wild-type (C/C)	Homozygosity (C/C)	30%	2
Heterozygosity (C/A)	Heterozygosity (A/C)	10%	3
Homozygosity (A/A)	Wild-type (A/A)	<5%	3