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Overlapping patterns of IGF2 and H19 expression during human development: biallelic IGF2 expression correlates with a lack of H19 expression.

R Ohlsson·F Hedborg·L Holmgren·C Walsh·T J Ekström
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Abstract

The spatial patterns of IGF2 and H19 gene expression are strikingly similar during parts of human embryonic/fetal and early postnatal development. Notable exceptions were found with the ciliary anlage of the embryonic retina and the choroid plexus/leptomeninges, where transcripts from the IGF2 but not the H19 locus could be detected. Moreover, in contrast to the other tissue samples examined, the choroid plexus/leptomeninges expressed both parental IGF2 alleles. Whilst RNase protection analysis revealed a weak activity of the P1 promoter in the choroid plexus/leptomeninges, the P2, P3 and P4 promoters were all active wherever IGF2 was expressed. We discuss these observations with respect to a hypothesized coordinated control of the reciprocally imprinted and closely linked IGF2 and H19 loci.

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AllelesChoroid PlexusEmbryonic and Fetal DevelopmentGene ExpressionHumansIn Situ HybridizationInfantInfant, NewbornLiverJournal ArticleResearch Support, Non-U.S. Gov't

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R Ohlsson, F Hedborg, L Holmgren, C Walsh, T J Ekström. 1994. Overlapping patterns of IGF2 and H19 expression during human development: biallelic IGF2 expression correlates with a lack of H19 expression.. https://doi.org/10.1242/dev.120.2.361

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