Table 3.

Single nucleotide polymorphism associated with traits before drug ingestion.

Drug	Duration	Reference SNPs	Genes	Effect	Cohort origin or ethnicity/PCOS criteria	No. PCOS patients	Ref.
Metformin 850 mg/d at dinner time	12 months	rs8111699	STK11	G allele was associated with higher insulin and IGF-I levels (p < 0.005).	Caucasian Northern Spanish girls/NS	85 (36 PCOS)	(90)
NA	NA	rs12208357 rs34447885 rs34104736 rs683369 rs34059508 rs36103319 rs628031	SLC22A1	Higher C-peptide levels at baseline and after glucose load found in patients with at least one mutant allele in SLC22A1 and SLC22A2 polymorphisms (p < 0.05). This hold true in a subsequent grouping among PCOS lean group (p =0.007).	Austria Caucasians/Rotterdam criteria	422	(94)
		rs316019	SLC22A2
		rs11212617	ATM

NA, not available; NS, not stated.