title: Inactivation of the mouse Huntington's disease gene homolog Hdh.
abstract: Huntington's disease (HD) is a dominant neurodegenerative disorder caused by expansion of a CAG repeat in the gene encoding huntingtin, a protein of unknown function. To distinguish between "loss of function" and "gain of function" models of HD, the murine HD homolog Hdh was inactivated by gene targeting. Mice heterozygous for Hdh inactivation were phenotypically normal, whereas homozygosity resulted in embryonic death. Homozygotes displayed abnormal gastrulation at embryonic day 7.5 and were resorbing by day 8.5. Thus, huntingtin is critical early in embryonic development, before the emergence of the nervous system. That Hdh inactivation does not mimic adult HD neuropathology suggests that the human disease involves a gain of function.
authors.affiliation: Molecular Neurogenetics Unit, Massachusetts General Hospital, Charlestown 02129, USA.
authors.forename: M P
authors.initials: MP
authors.lastname: Duyao
authors.forename: A B
authors.initials: AB
authors.lastname: Auerbach
authors.forename: A
authors.initials: A
authors.lastname: Ryan
authors.forename: F
authors.initials: F
authors.lastname: Persichetti
authors.forename: G T
authors.initials: GT
authors.lastname: Barnes
authors.forename: S M
authors.initials: SM
authors.lastname: McNeil
authors.forename: P
authors.initials: P
authors.lastname: Ge
authors.forename: J P
authors.initials: JP
authors.lastname: Vonsattel
authors.forename: J F
authors.initials: JF
authors.lastname: Gusella
authors.forename: A L
authors.initials: AL
authors.lastname: Joyner
mesh_terms: D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D004475:Ectoderm / Q000166:cytology; D005314:Embryonic and Fetal Development; D005260:Female; D018390:Gene Targeting; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D000071058:Huntingtin Protein; D006816:Huntington Disease / Q000235:genetics*; D008297:Male; D008648:Mesoderm / Q000166:cytology; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000502:physiology; D009687:Nuclear Proteins / Q000235:genetics* / Q000502:physiology; D010641:Phenotype; D013234:Stem Cells / Q000378:metabolism
chemical_list: C086055:HTT protein, human; C506812:Htt protein, mouse; D000071058:Huntingtin Protein; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins