Table 4.

Stratified association between rare non-synonymous variants of ABCG2 and gout susceptibility by common variants of ABCG2, Q126X and Q141K

	Case			Control
Sample set	Number	Carrier*	Frequency (%)†	Number	Carrier*	Frequency (%)†	p Value	OR (95% CI)
All	480	30	6.3	480	15	3.1	0.022	2.1 (1.1 to 3.9)
Without Q126X	425	30	7.1	457	15	3.3	0.011	2.2 (1.2 to 4.2)
Without Q126X or Q141K	131	14	10.7	247	9	3.6	6.4×10-3	3.2 (1.3 to 7.5)

Only non-synonymous SNVs or indels with minor allele frequency less than 1% were considered rare non-synonymous variants in this analysis.

Since the P268S variant of ABCG2 did not decrease urate transport activity, it was excluded from this analysis.

The A149P variant of ABCG2 was also excluded from this analysis due to its scores of SIFT and PolyPhen-2 as well as a previous report of functional analysis.¹⁸

*The number of carriers with rare non-synonymous variants of ABCG2.

†The percentage of cases or controls carrying rare non-synonymous variants of ABCG2.

ABCG2, ATP-binding cassette transporter subfamily G member 2; indels, short insertions and deletions; PolyPhen-2, Polymorphism Phenotyping v2; SIFT, Sorting Intolerant from Tolerant; SNVs, single nucleotide variants.