title: Parental effect of DNA (Cytosine-5) methyltransferase 1 on grandparental-origin-dependent transmission ratio distortion in mouse crosses and human families.
abstract: Transmission ratio distortion (TRD) is a deviation from the expected Mendelian 1:1 ratio of alleles transmitted from parents to offspring and may arise by different mechanisms. Earlier we described a grandparental-origin-dependent sex-of-offspring-specific TRD of maternal chromosome 12 alleles closely linked to an imprinted region and hypothesized that it resulted from imprint resetting errors in the maternal germline. Here, we report that the genotype of the parents for loss-of-function mutations in the Dnmt1 gene influences the transmission of grandparental chromosome 12 alleles. More specifically, maternal Dnmt1 mutations restore Mendelian transmission ratios of chromosome 12 alleles. Transmission of maternal alleles depends upon the presence of the Dnmt1 mutation in the mother rather than upon the Dnmt1 genotype of the offspring. Paternal transmission mirrors the maternal one: live-born offspring of wild-type fathers display 1:1 transmission ratios, whereas offspring of heterozygous Dnmt1 mutant fathers tend to inherit grandpaternal alleles. Analysis of allelic transmission in the homologous region of human chromosome 14q32 detected preferential transmission of alleles from the paternal grandfather to grandsons. Thus, parental Dnmt1 is a modifier of transmission of alleles at an unlinked chromosomal region and perhaps has a role in the genesis of TRD.
authors.affiliation: Department of Human Genetics, Faculty of Medicine, McGill University Montreal, Quebec, Canada.
authors.forename: Lanjian
authors.initials: L
authors.lastname: Yang
authors.forename: Moises Freitas
authors.initials: MF
authors.lastname: Andrade
authors.forename: Stephane
authors.initials: S
authors.lastname: Labialle
authors.forename: Sanny
authors.initials: S
authors.lastname: Moussette
authors.forename: Geneviève
authors.initials: G
authors.lastname: Geneau
authors.forename: Donna
authors.initials: D
authors.lastname: Sinnett
authors.forename: Alexandre
authors.initials: A
authors.lastname: Belisle
authors.forename: Celia M T
authors.initials: CM
authors.lastname: Greenwood
authors.forename: Anna K
authors.initials: AK
authors.lastname: Naumova
mesh_terms: D000483:Alleles; D000818:Animals; D033481:Chromosomes, Mammalian / Q000235:genetics; D003433:Crosses, Genetic; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics / Q000378:metabolism*; D019175:DNA Methylation; D005190:Family; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D018392:Genomic Imprinting / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D040582:Inheritance Patterns / Q000235:genetics*; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009154:Mutation / Q000235:genetics; D009865:Oocytes / Q000201:enzymology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013094:Spermatozoa / Q000201:enzymology; D013737:Testis / Q000201:enzymology
chemical_list: D007527:Isoenzymes; D012333:RNA, Messenger; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; C000619380:DNMT1 protein, human; C000619381:Dnmt1 protein, mouse