It is indeed true that Impact is a paternally expressed imprinted gene (http://www.ncbi.nlm.nih.g...), and we did cite this paper as Reference # 29. We also show this fact correctly in supporting Figure 1.9 and Table 1. Unfortunately there was a typographical error in the text, which we will correct in an addendum. Thanks for catching this.
Regarding H19, we already cited the commenter’s noted paper as Reference # 30. Please note that this paper reported the imprinting status of H19 in fetal brain, not neonatal brain.
For Cdkn1c, in this paper, we find that “Cdkn1c is faithfully imprinted in all mouse tissues in which it is expressed, from early embryonic development through adulthood.” But the paper is silent on specific experimental evidence regarding whether Cdkn1c is imprinted in neonatal brain. The title of this paper is “Elongation of the Kcnq1ot1 transcript is required for genomic imprinting of neighboring genes”.
We already mentioned that the last 5 genes mentioned in the comment are known imprinted genes in mouse. Since most imprinted genes show some degree of tissue- or developmental stage-specific expression, especially in placenta and different stages of brains (fetal brain, neonatal brain and adult brain). We are saying that the imprinting status in neonatal brain had not been unambiguously reported in the literature.