title: Epigenetic heterogeneity at imprinted loci in normal populations.
abstract: Genomic imprinting is the phenomenon by which the two alleles of certain genes are differentially expressed according to their parental origin. Extensive analysis of allelic expression at multiple imprinted loci in a normal population has not performed so far. In the present study, we examined the allelic expression pattern of three imprinted genes in a panel of 262 Japanese normal individuals. We observed differences in the extent of maintenance of allele-specific expression of the three genes. The allelic expression of small nuclear ribonucleoprotein N (SNRPN) was stringently regulated while that of multimembrane-spanning polyspecific transporter-like gene 1 (IMPT1) showed a large degree of variation. Significant biallelic expression of insulin-like growth factor II (IGF2) was observed in about 10% of normal individuals. Our findings add to the accumulating evidence for variable allelic expression at multiple loci in a normal human population. This epigenetic heterogeneity can be a stable trait and potentially influence individual phenotypes.
authors.affiliation: CREST Program of the Japan Science and Technology Corporation (JST), Tottori University, Yonago, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sakatani
authors.forename: M
authors.initials: M
authors.lastname: Wei
authors.forename: M
authors.initials: M
authors.lastname: Katoh
authors.forename: C
authors.initials: C
authors.lastname: Okita
authors.forename: D
authors.initials: D
authors.lastname: Wada
authors.forename: K
authors.initials: K
authors.lastname: Mitsuya
authors.forename: M
authors.initials: M
authors.lastname: Meguro
authors.forename: M
authors.initials: M
authors.lastname: Ikeguchi
authors.forename: H
authors.initials: H
authors.lastname: Ito
authors.forename: B
authors.initials: B
authors.lastname: Tycko
authors.forename: M
authors.initials: M
authors.lastname: Oshimura
mesh_terms: D000483:Alleles; D001324:Autoantigens / Q000235:genetics*; D004247:DNA / Q000097:blood; D005260:Female; D005786:Gene Expression Regulation; D014644:Genetic Variation; D018392:Genomic Imprinting; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D007564:Japan; D007962:Leukocytes / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D027701:Organic Cation Transport Proteins; D010375:Pedigree; D016133:Polymerase Chain Reaction; D017411:Ribonucleoproteins, Small Nuclear / Q000235:genetics; D055517:snRNP Core Proteins
chemical_list: D001324:Autoantigens; D008565:Membrane Proteins; D027701:Organic Cation Transport Proteins; D017411:Ribonucleoproteins, Small Nuclear; C111653:SLC22A18 protein, human; C526417:SNRPN protein, human; D055517:snRNP Core Proteins; D007335:Insulin-Like Growth Factor II; D004247:DNA