Figure 1.

Methyl supplementation prevents transgenerational increase in adult body weight. (a) Genogram illustrating study design; a/a mice are shown in black and A^vy/a mice in various shades of yellow/brown. (b) Body weight at weaning (P21) in a/a and A^vy/a offspring born to A^vy/a females (n_total=119 (F1), 214 (F2) and 379 (F3)). Box plots indicate median, 25th—75th percentiles (box), and 5th—95th percentiles (whiskers). In unsupplemented A^vy/a offspring only, P21 weight increases with successive generations (P=0.007). (c) Distribution of adult (P180) body weight of A^vy/a offspring by generation and group (n_unsuppl=29 (F1), 36 (F2) and 88 (F3); n_suppl=33 (F1), 62 (F2) and 117 (F3)). The percentages in each panel indicate the proportion of offspring above 50 g (dotted line). Body weight is relatively constant in the supplemented group, but increases transgenerationally in the unsupplemented group (P=0.000006). (d) P180 body weight versus coat color class for A^vy/a animals in the F3 generation (1 = yellow, 2 = slightly mottled, 3 = mottled, 4 = heavily mottled; number of mice in each class is indicated). Body coat color class. weight is not associated with A^vy epigenotype. Supplemented mice tend to weigh less within every coat color class.