Longitudinal stability in reading comprehension is largely heritable from grades 1 to 6.
Soden B, Christopher ME, Hulslander J, Olson RK, Cutting L, Keenan JM, Thompson LA, Wadsworth SJ, Willcutt EG, Petrill SA. Longitudinal stability in reading comprehension is largely heritable from grades 1 to 6. PLoS One. 2015; 10(1):e0113807.