ID	group	group2
YC_R1	YC	young_control
YC_R2	YC	young_control
YE_R1	YE	young_enriched
YE_R2	YE	young_enriched
OC_R1	OC	old_control
OC_R2	OC	old_control
OE_R1	OE	old_enriched
OE_R2	OE	old_enriched