Table 2. Differential Methylation Across Generation, Sex, and Dose in Liver by RRBS Data.

Liver tissue from F1 and F2 offspring at exposures 10 ppb and 245 ppb were assessed for differential DNA methylation as a result of in utero exposure. RRBS differential methylation was identified by DSS package in R studio. Statistical significance was determined by running a Wald Test in DSS, where data displayed have a p-value threshold set to FDR <0.001 (n= 3 per treatment, per sex).

F1 Generation: DMC and DMR count in Female and Male Offspring
Differentially Methylated CpGs (DMCs)
5mC	10 ppb iAs				245 ppb iAs
	Female		Male		Female		Male
Hypermethylated	259	66%	299	65%	157	61%	265	64%
Hypomethylated	132	34%	196	42%	99	39%	151	36%
Total	391		462		256		416
Differentially Methylated Regions (DMRs)
5mC	10 ppb iAs				245 ppb iAs
	Female		Male		Female		Male
Hypermethylated	4	80%	3	43%	-	0%	9	82%
Hypomethylated	1	20%	4	57%	-	0%	2	18%
Total	5		7		-		11
F2 Generation: DMC and DMR count in Female and Male Grand-Offspring
Differentially Methylated CpGs (DMCs)
5mC	10 ppb iAs				245 ppb iAs
	Female		Male		Female		Male
Hypermethylated	320	60%	140	54%	156	43%	144	52%
Hypomethylated	217	40%	118	46%	208	57%	133	48%
Total	537		258		364		277
Differentially Methylated Regions (DMRs)
5mC	10 ppb iAs				245 ppb iAs
	Female		Male		Female		Male
Hypermethylated	9	56%	1	100%	1	20%	1	100%
Hypomethylated	7	44%	-		4	80%	-
Total	16		1		5		1