title: Assessment of MDA efficiency for genotyping using cloned embryo biopsies.
abstract: The possibility to genotype embryos prior to implantation would have advantages for increasing the speed of selection of cattle. Reliable genotyping requires more DNA than can be obtained from biopsies of embryos, if they are to remain viable. Multiple displacement amplification (MDA) is a whole genome amplification technique used to increase the amount of DNA from biopsies for analysis. Reduced genome coverage resulting in Allele Drop Out (ADO) at heterozygous loci or missing genotypes are drawbacks of MDA. The present article describes the correlation between the input DNA quantity or embryo biopsy size and MDA success. Missing genotypes and ADO drastically increased when fewer than 30-40 cells or the genomic equivalents were used. However, embryo viability was found to be reduced if biopsied with more than 10 cells. Therefore, in vitro cell culture was investigated as a means to increase the number of cells available and the genotyping reliability.
authors.affiliation: Parco Tecnologico Padano, Via Einstein, Lodi, Italy. andrea.lauri@tecnoparco.org
authors.forename: Andrea
authors.initials: A
authors.lastname: Lauri
authors.forename: Giovanna
authors.initials: G
authors.lastname: Lazzari
authors.forename: Cesare
authors.initials: C
authors.lastname: Galli
authors.forename: Irina
authors.initials: I
authors.lastname: Lagutina
authors.forename: Elena
authors.initials: E
authors.lastname: Genzini
authors.forename: Francesco
authors.initials: F
authors.lastname: Braga
authors.forename: Paola
authors.initials: P
authors.lastname: Mariani
authors.forename: John L
authors.initials: JL
authors.lastname: Williams
mesh_terms: D000483:Alleles; D000818:Animals; D001706:Biopsy; D002417:Cattle / Q000196:embryology / Q000235:genetics*; D019976:Cloning, Organism; D004622:Embryo, Mammalian / Q000737:chemistry / Q000473:pathology; D005838:Genotype; D060005:Genotyping Techniques; D021141:Nucleic Acid Amplification Techniques; D017422:Sequence Analysis, DNA